Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Clang-19 crash:/lib/AST/ExprConstant.cpp:1633: void {anonymous}::LValue::setFrom(clang::ASTContext&, const clang::APValue&): Assertion `V.isLValue() && "Setting LValue from a non-LValue?"' failed. #95366

Closed
iamanonymouscs opened this issue Jun 13, 2024 · 9 comments · Fixed by #95479
Closed

Clang-19 crash:/lib/AST/ExprConstant.cpp:1633: void {anonymous}::LValue::setFrom(clang::ASTContext&, const clang::APValue&): Assertion `V.isLValue() && "Setting LValue from a non-LValue?"' failed. #95366

iamanonymouscs opened this issue Jun 13, 2024 · 9 comments · Fixed by #95479
Assignees
@a-tarasyuk
Labels
clang:frontend Language frontend issues, e.g. anything involving "Sema" confirmed Verified by a second party constexpr Anything related to constant evaluation crash-on-valid good first issue https://github.com/llvm/llvm-project/contribute

Comments

@iamanonymouscs
Copy link

Description:

Encountered a segmentation fault (core dumped) error while compiling a C code snippet using Clang version 19.0.0 on Ubuntu.
The code snippet includes a function definition with a complex expression involving GNU extensions.

Also ICE on trunk, compiler explorer:https:https://godbolt.org/z/sc38GbqW4

OS and Platform:

# uname -a
Linux ubuntu 4.15.0-213-generic #224-Ubuntu SMP Mon Jun 19 13:30:12 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

# clang -v
Ubuntu clang version 19.0.0 (++20240301064251+dd426fa5f931-1~exp1~20240301184412.1845)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/lib/llvm-19/bin
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Candidate multilib: .;@m64
Selected multilib: .;@m64

Program:

# cat code_2.c

x() { &&e - &&b < x; }

Command Lines:

# clang code_2.c -O3 -fsanitize=undefined -Wall -Wextra -pedantic -Werror -std=c11 
code_2.c:1:1: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
    1 | x() { &&e - &&b < x; }
      | ^
      | int
code_2.c:1:2: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
    1 | x() { &&e - &&b < x; }
      |  ^
      |   void
code_2.c:1:7: error: use of GNU address-of-label extension [-Werror,-Wgnu-label-as-value]
    1 | x() { &&e - &&b < x; }
      |       ^
code_2.c:1:13: error: use of GNU address-of-label extension [-Werror,-Wgnu-label-as-value]
    1 | x() { &&e - &&b < x; }
      |             ^
code_2.c:1:11: error: arithmetic on pointers to void is a GNU extension [-Werror,-Wgnu-pointer-arith]
    1 | x() { &&e - &&b < x; }
      |       ~~~ ^ ~~~
code_2.c:1:17: error: ordered comparison between pointer and integer ('long' and 'int (*)()') [-Werror]
    1 | x() { &&e - &&b < x; }
      |       ~~~~~~~~~ ^ ~
code_2.c:1:17: error: relational comparison result unused [-Werror,-Wunused-comparison]
    1 | x() { &&e - &&b < x; }
      |       ~~~~~~~~~~^~~
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: /usr/lib/llvm-19/bin/clang -cc1 -triple x86_64-pc-linux-gnu -emit-obj -dumpdir a- -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name code_2.c -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323 -fcoverage-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323 -resource-dir /usr/lib/llvm-19/lib/clang/19 -internal-isystem /usr/lib/llvm-19/lib/clang/19/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wall -Wextra -Werror -pedantic -std=c11 -ferror-limit 19 -fsanitize=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound,vptr -fsanitize-recover=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,vla-bound,vptr -fno-sanitize-memory-param-retval -fno-sanitize-address-use-odr-indicator -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcolor-diagnostics -vectorize-loops -vectorize-slp -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/code_2-15394c.o -x c code_2.c
1.      code_2.c:1:22: current parser token '}'
2.      code_2.c:1:5: parsing function body 'x'
3.      code_2.c:1:5: in compound statement ('{}')
 #0 0x00007fa6de8c5216 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/usr/lib/llvm-19/bin/../lib/libLLVM.so.19.0+0xdc1216)
 #1 0x00007fa6de8c2ec0 llvm::sys::RunSignalHandlers() (/usr/lib/llvm-19/bin/../lib/libLLVM.so.19.0+0xdbeec0)
 #2 0x00007fa6de8c58f0 (/usr/lib/llvm-19/bin/../lib/libLLVM.so.19.0+0xdc18f0)
 #3 0x00007fa6e92b4980 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x12980)
 #4 0x00007fa6e609b05e clang::Decl::getASTContext() const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xe3e05e)
 #5 0x00007fa6e608ae4f clang::NamedDecl::printName(llvm::raw_ostream&) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xe2de4f)
 #6 0x00007fa6e5ee32d6 clang::APValue::printPretty(llvm::raw_ostream&, clang::PrintingPolicy const&, clang::QualType, clang::ASTContext const*) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc862d6)
 #7 0x00007fa6e5ee3bd6 clang::APValue::getAsString[abi:cxx11](clang::ASTContext const&, clang::QualType) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc86bd6)
 #8 0x00007fa6e6178f6d (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xf1bf6d)
 #9 0x00007fa6e6171fe6 (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xf14fe6)
#10 0x00007fa6e611bb07 (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xebeb07)
#11 0x00007fa6e6119420 (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xebc420)
#12 0x00007fa6e611984e clang::Expr::EvaluateForOverflow(clang::ASTContext const&) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xebc84e)
#13 0x00007fa6e674c8ec clang::Sema::CheckForIntOverflow(clang::Expr const*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x14ef8ec)
#14 0x00007fa6e674d1f5 clang::Sema::CheckCompletedExpr(clang::Expr*, clang::SourceLocation, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x14f01f5)
#15 0x00007fa6e6abaca6 clang::Sema::ActOnFinishFullExpr(clang::Expr*, clang::SourceLocation, bool, bool, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x185dca6)
#16 0x00007fa6e6ca233a clang::Sema::ActOnExprStmt(clang::ActionResult<clang::Expr*, true>, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x1a4533a)
#17 0x00007fa6e5eb58f6 clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::ParsedAttributes&, clang::ParsedAttributes&) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc588f6)
#18 0x00007fa6e5eb52cb clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc582cb)
#19 0x00007fa6e5ebdc80 clang::Parser::ParseCompoundStatementBody(bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc60c80)
#20 0x00007fa6e5ebedef clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc61def)
#21 0x00007fa6e5ed8c36 clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::LateParsedAttrList*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7bc36)
#22 0x00007fa6e5e233a7 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::ParsedAttributes&, clang::Parser::ParsedTemplateInfo&, clang::SourceLocation*, clang::Parser::ForRangeInit*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xbc63a7)
#23 0x00007fa6e5ed7cb4 clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec&, clang::AccessSpecifier) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7acb4)
#24 0x00007fa6e5ed769b clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*, clang::AccessSpecifier) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7a69b)
#25 0x00007fa6e5ed68ed clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc798ed)
#26 0x00007fa6e5ed4d3c clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc77d3c)
#27 0x00007fa6e5ed469f clang::Parser::ParseFirstTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7769f)
#28 0x00007fa6e5e0d006 clang::ParseAST(clang::Sema&, bool, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xbb0006)
#29 0x00007fa6e7d0a825 clang::FrontendAction::Execute() (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x2aad825)
#30 0x00007fa6e7c860d4 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x2a290d4)
#31 0x00007fa6e7d83f7e clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x2b26f7e)
#32 0x000055c9cda4afad cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/usr/lib/llvm-19/bin/clang+0x12fad)
#33 0x000055c9cda48075 (/usr/lib/llvm-19/bin/clang+0x10075)
#34 0x000055c9cda47213 clang_main(int, char**, llvm::ToolContext const&) (/usr/lib/llvm-19/bin/clang+0xf213)
#35 0x000055c9cda55556 main (/usr/lib/llvm-19/bin/clang+0x1d556)
#36 0x00007fa6dcdf5c87 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21c87)
#37 0x000055c9cda44bfa _start (/usr/lib/llvm-19/bin/clang+0xcbfa)
clang: error: unable to execute command: Segmentation fault (core dumped)
clang: error: clang frontend command failed due to signal (use -v to see invocation)
Ubuntu clang version 19.0.0 (++20240301064251+dd426fa5f931-1~exp1~20240301184412.1845)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/lib/llvm-19/bin
clang: note: diagnostic msg: 
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang: note: diagnostic msg: /tmp/code_2-af78db.c
clang: note: diagnostic msg: /tmp/code_2-af78db.sh
clang: note: diagnostic msg: 

********************

# cat /tmp/code_2-af78db.c
# 1 "<built-in>"
# 1 "code_2.c"
x() { &&e - &&b < x; }



# cat /tmp/code_2-af78db.sh
# Crash reproducer for Ubuntu clang version 19.0.0 (++20240301064251+dd426fa5f931-1~exp1~20240301184412.1845)
# Driver args: "code_2.c" "-O3" "-fsanitize=undefined" "-Wall" "-Wextra" "-pedantic" "-Werror" "-std=c11"
# Original command:  "/usr/lib/llvm-19/bin/clang" "-cc1" "-triple" "x86_64-pc-linux-gnu" "-emit-obj" "-dumpdir" "a-" "-disable-free" "-clear-ast-before-backend" "-disable-llvm-verifier" "-discard-value-names" "-main-file-name" "code_2.c" "-mrelocation-model" "pic" "-pic-level" "2" "-pic-is-pie" "-mframe-pointer=none" "-fmath-errno" "-ffp-contract=on" "-fno-rounding-math" "-mconstructor-aliases" "-funwind-tables=2" "-target-cpu" "x86-64" "-tune-cpu" "generic" "-debugger-tuning=gdb" "-fdebug-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-fcoverage-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-resource-dir" "/usr/lib/llvm-19/lib/clang/19" "-internal-isystem" "/usr/lib/llvm-19/lib/clang/19/include" "-internal-isystem" "/usr/local/include" "-internal-isystem" "/usr/lib/gcc/x86_64-linux-gnu/7/../../../../x86_64-linux-gnu/include" "-internal-externc-isystem" "/usr/include/x86_64-linux-gnu" "-internal-externc-isystem" "/include" "-internal-externc-isystem" "/usr/include" "-O3" "-Wall" "-Wextra" "-Werror" "-pedantic" "-std=c11" "-ferror-limit" "19" "-fsanitize=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound,vptr" "-fsanitize-recover=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,vla-bound,vptr" "-fno-sanitize-memory-param-retval" "-fno-sanitize-address-use-odr-indicator" "-fgnuc-version=4.2.1" "-fskip-odr-check-in-gmf" "-fcolor-diagnostics" "-vectorize-loops" "-vectorize-slp" "-faddrsig" "-D__GCC_HAVE_DWARF2_CFI_ASM=1" "-o" "/tmp/code_2-15394c.o" "-x" "c" "code_2.c"
 "/usr/lib/llvm-19/bin/clang" "-cc1" "-triple" "x86_64-pc-linux-gnu" "-emit-obj" "-dumpdir" "a-" "-disable-free" "-clear-ast-before-backend" "-disable-llvm-verifier" "-discard-value-names" "-main-file-name" "code_2.c" "-mrelocation-model" "pic" "-pic-level" "2" "-pic-is-pie" "-mframe-pointer=none" "-fmath-errno" "-ffp-contract=on" "-fno-rounding-math" "-mconstructor-aliases" "-funwind-tables=2" "-target-cpu" "x86-64" "-tune-cpu" "generic" "-debugger-tuning=gdb" "-fdebug-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-fcoverage-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-O3" "-Wall" "-Wextra" "-Werror" "-pedantic" "-std=c11" "-ferror-limit" "19" "-fsanitize=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound,vptr" "-fsanitize-recover=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,vla-bound,vptr" "-fno-sanitize-memory-param-retval" "-fno-sanitize-address-use-odr-indicator" "-fgnuc-version=4.2.1" "-fskip-odr-check-in-gmf" "-fcolor-diagnostics" "-vectorize-loops" "-vectorize-slp" "-faddrsig" "-D__GCC_HAVE_DWARF2_CFI_ASM=1" "-x" "c" "code_2-af78db.c"
@github-actions github-actions bot added the clang Clang issues not falling into any other category label Jun 13, 2024
@zyn0217
Copy link
Contributor

zyn0217 commented Jun 13, 2024

The code looks really weird to me; did you get the code from a fuzzer or from a reduction of something?

@iamanonymouscs
Copy link
Author

The code looks really weird to me; did you get the code from a fuzzer or from a reduction of something?

The code snippet is obtained from a previous report that caused a compiler crash. After being processed by Creduce, it may indeed be a bit odd.

@tbaederr tbaederr added the constexpr Anything related to constant evaluation label Jun 13, 2024
@AaronBallman AaronBallman added the confirmed Verified by a second party label Jun 13, 2024
@AaronBallman
Copy link
Collaborator

This is actually a crash-on-valid though the code from the OP is invalid. Here's a repaired example that still crashes:

int x(void) { e: b: ; return &&e - &&b < x; }

https://godbolt.org/z/b5eP9szvx

@tbaederr
Copy link
Contributor

tbaederr commented Jun 13, 2024 •
edited
Loading

The LHS of the < operator gets converted to a pointer:

ImplicitCastExpr 0x52100006daf8 'int (*)(void)' <IntegralToPointer>
`-BinaryOperator 0x52100006d578 'long' '-'
  |-AddrLabelExpr 0x52100006d528 'void *' e 0x52100006d4a8
  `-AddrLabelExpr 0x52100006d550 'void *' b 0x52100006d428

but evaluating the BinaryOperator doesn't result in an integer APValue like it (seems it) should, it results in a AddrLabelDiff. So we hit the else case here:

llvm-project/clang/lib/AST/ExprConstant.cpp

Lines 9318 to 9331 in ae73706

if (Value.isInt()) {
unsigned Size = Info.Ctx.getTypeSize(E->getType());
uint64_t N = Value.getInt().extOrTrunc(Size).getZExtValue();
Result.Base = (Expr*)nullptr;
Result.InvalidBase = false;
Result.Offset = CharUnits::fromQuantity(N);
Result.Designator.setInvalid();
Result.IsNullPtr = false;
return true;
} else {
// Cast is of an lvalue, no need to change value.
Result.setFrom(Info.Ctx, Value);
return true;
}

@tbaederr
Copy link
Contributor

Seems like we should just do a Value.isLValue() check here and reject this comparison.

@tbaederr tbaederr added the good first issue https://github.com/llvm/llvm-project/contribute label Jun 13, 2024
@llvmbot
Copy link
Member

llvmbot commented Jun 13, 2024

Hi!

This issue may be a good introductory issue for people new to working on LLVM. If you would like to work on this issue, your first steps are:

  1. Check that no other contributor has already been assigned to this issue. If you believe that no one is actually working on it despite an assignment, ping the person. After one week without a response, the assignee may be changed.
  2. In the comments of this issue, request for it to be assigned to you, or just create a pull request after following the steps below. Mention this issue in the description of the pull request.
  3. Fix the issue locally.
  4. Run the test suite locally. Remember that the subdirectories under test/ create fine-grained testing targets, so you can e.g. use make check-clang-ast to only run Clang's AST tests.
  5. Create a Git commit.
  6. Run git clang-format HEAD~1 to format your changes.
  7. Open a pull request to the upstream repository on GitHub. Detailed instructions can be found in GitHub's documentation. Mention this issue in the description of the pull request.

If you have any further questions about this issue, don't hesitate to ask via a comment in the thread below.

@llvmbot
Copy link
Member

llvmbot commented Jun 13, 2024

@llvm/issue-subscribers-good-first-issue

Author: Anonymous (iamanonymouscs)

### Description: Encountered a segmentation fault (core dumped) error while compiling a C code snippet using Clang version 19.0.0 on Ubuntu. The code snippet includes a function definition with a complex expression involving GNU extensions.

Also ICE on trunk, compiler explorer:https:https://godbolt.org/z/sc38GbqW4

OS and Platform:

# uname -a
Linux ubuntu 4.15.0-213-generic #<!-- -->224-Ubuntu SMP Mon Jun 19 13:30:12 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

# clang -v
Ubuntu clang version 19.0.0 (++20240301064251+dd426fa5f931-1~exp1~20240301184412.1845)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/lib/llvm-19/bin
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Candidate multilib: .;@<!-- -->m64
Selected multilib: .;@<!-- -->m64

Program:

# cat code_2.c

x() { &amp;&amp;e - &amp;&amp;b &lt; x; }

Command Lines:

# clang code_2.c -O3 -fsanitize=undefined -Wall -Wextra -pedantic -Werror -std=c11 
code_2.c:1:1: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      | ^
      | int
code_2.c:1:2: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |  ^
      |   void
code_2.c:1:7: error: use of GNU address-of-label extension [-Werror,-Wgnu-label-as-value]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |       ^
code_2.c:1:13: error: use of GNU address-of-label extension [-Werror,-Wgnu-label-as-value]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |             ^
code_2.c:1:11: error: arithmetic on pointers to void is a GNU extension [-Werror,-Wgnu-pointer-arith]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |       ~~~ ^ ~~~
code_2.c:1:17: error: ordered comparison between pointer and integer ('long' and 'int (*)()') [-Werror]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |       ~~~~~~~~~ ^ ~
code_2.c:1:17: error: relational comparison result unused [-Werror,-Wunused-comparison]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |       ~~~~~~~~~~^~~
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: /usr/lib/llvm-19/bin/clang -cc1 -triple x86_64-pc-linux-gnu -emit-obj -dumpdir a- -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name code_2.c -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323 -fcoverage-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323 -resource-dir /usr/lib/llvm-19/lib/clang/19 -internal-isystem /usr/lib/llvm-19/lib/clang/19/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wall -Wextra -Werror -pedantic -std=c11 -ferror-limit 19 -fsanitize=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound,vptr -fsanitize-recover=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,vla-bound,vptr -fno-sanitize-memory-param-retval -fno-sanitize-address-use-odr-indicator -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcolor-diagnostics -vectorize-loops -vectorize-slp -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/code_2-15394c.o -x c code_2.c
1.      code_2.c:1:22: current parser token '}'
2.      code_2.c:1:5: parsing function body 'x'
3.      code_2.c:1:5: in compound statement ('{}')
 #<!-- -->0 0x00007fa6de8c5216 llvm::sys::PrintStackTrace(llvm::raw_ostream&amp;, int) (/usr/lib/llvm-19/bin/../lib/libLLVM.so.19.0+0xdc1216)
 #<!-- -->1 0x00007fa6de8c2ec0 llvm::sys::RunSignalHandlers() (/usr/lib/llvm-19/bin/../lib/libLLVM.so.19.0+0xdbeec0)
 #<!-- -->2 0x00007fa6de8c58f0 (/usr/lib/llvm-19/bin/../lib/libLLVM.so.19.0+0xdc18f0)
 #<!-- -->3 0x00007fa6e92b4980 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x12980)
 #<!-- -->4 0x00007fa6e609b05e clang::Decl::getASTContext() const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xe3e05e)
 #<!-- -->5 0x00007fa6e608ae4f clang::NamedDecl::printName(llvm::raw_ostream&amp;) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xe2de4f)
 #<!-- -->6 0x00007fa6e5ee32d6 clang::APValue::printPretty(llvm::raw_ostream&amp;, clang::PrintingPolicy const&amp;, clang::QualType, clang::ASTContext const*) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc862d6)
 #<!-- -->7 0x00007fa6e5ee3bd6 clang::APValue::getAsString[abi:cxx11](clang::ASTContext const&amp;, clang::QualType) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc86bd6)
 #<!-- -->8 0x00007fa6e6178f6d (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xf1bf6d)
 #<!-- -->9 0x00007fa6e6171fe6 (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xf14fe6)
#<!-- -->10 0x00007fa6e611bb07 (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xebeb07)
#<!-- -->11 0x00007fa6e6119420 (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xebc420)
#<!-- -->12 0x00007fa6e611984e clang::Expr::EvaluateForOverflow(clang::ASTContext const&amp;) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xebc84e)
#<!-- -->13 0x00007fa6e674c8ec clang::Sema::CheckForIntOverflow(clang::Expr const*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x14ef8ec)
#<!-- -->14 0x00007fa6e674d1f5 clang::Sema::CheckCompletedExpr(clang::Expr*, clang::SourceLocation, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x14f01f5)
#<!-- -->15 0x00007fa6e6abaca6 clang::Sema::ActOnFinishFullExpr(clang::Expr*, clang::SourceLocation, bool, bool, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x185dca6)
#<!-- -->16 0x00007fa6e6ca233a clang::Sema::ActOnExprStmt(clang::ActionResult&lt;clang::Expr*, true&gt;, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x1a4533a)
#<!-- -->17 0x00007fa6e5eb58f6 clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector&lt;clang::Stmt*, 32u&gt;&amp;, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc588f6)
#<!-- -->18 0x00007fa6e5eb52cb clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector&lt;clang::Stmt*, 32u&gt;&amp;, clang::Parser::ParsedStmtContext, clang::SourceLocation*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc582cb)
#<!-- -->19 0x00007fa6e5ebdc80 clang::Parser::ParseCompoundStatementBody(bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc60c80)
#<!-- -->20 0x00007fa6e5ebedef clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&amp;) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc61def)
#<!-- -->21 0x00007fa6e5ed8c36 clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&amp;, clang::Parser::ParsedTemplateInfo const&amp;, clang::Parser::LateParsedAttrList*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7bc36)
#<!-- -->22 0x00007fa6e5e233a7 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&amp;, clang::DeclaratorContext, clang::ParsedAttributes&amp;, clang::Parser::ParsedTemplateInfo&amp;, clang::SourceLocation*, clang::Parser::ForRangeInit*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xbc63a7)
#<!-- -->23 0x00007fa6e5ed7cb4 clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;, clang::ParsingDeclSpec&amp;, clang::AccessSpecifier) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7acb4)
#<!-- -->24 0x00007fa6e5ed769b clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;, clang::ParsingDeclSpec*, clang::AccessSpecifier) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7a69b)
#<!-- -->25 0x00007fa6e5ed68ed clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;, clang::ParsingDeclSpec*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc798ed)
#<!-- -->26 0x00007fa6e5ed4d3c clang::Parser::ParseTopLevelDecl(clang::OpaquePtr&lt;clang::DeclGroupRef&gt;&amp;, clang::Sema::ModuleImportState&amp;) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc77d3c)
#<!-- -->27 0x00007fa6e5ed469f clang::Parser::ParseFirstTopLevelDecl(clang::OpaquePtr&lt;clang::DeclGroupRef&gt;&amp;, clang::Sema::ModuleImportState&amp;) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7769f)
#<!-- -->28 0x00007fa6e5e0d006 clang::ParseAST(clang::Sema&amp;, bool, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xbb0006)
#<!-- -->29 0x00007fa6e7d0a825 clang::FrontendAction::Execute() (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x2aad825)
#<!-- -->30 0x00007fa6e7c860d4 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&amp;) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x2a290d4)
#<!-- -->31 0x00007fa6e7d83f7e clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x2b26f7e)
#<!-- -->32 0x000055c9cda4afad cc1_main(llvm::ArrayRef&lt;char const*&gt;, char const*, void*) (/usr/lib/llvm-19/bin/clang+0x12fad)
#<!-- -->33 0x000055c9cda48075 (/usr/lib/llvm-19/bin/clang+0x10075)
#<!-- -->34 0x000055c9cda47213 clang_main(int, char**, llvm::ToolContext const&amp;) (/usr/lib/llvm-19/bin/clang+0xf213)
#<!-- -->35 0x000055c9cda55556 main (/usr/lib/llvm-19/bin/clang+0x1d556)
#<!-- -->36 0x00007fa6dcdf5c87 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21c87)
#<!-- -->37 0x000055c9cda44bfa _start (/usr/lib/llvm-19/bin/clang+0xcbfa)
clang: error: unable to execute command: Segmentation fault (core dumped)
clang: error: clang frontend command failed due to signal (use -v to see invocation)
Ubuntu clang version 19.0.0 (++20240301064251+dd426fa5f931-1~exp1~20240301184412.1845)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/lib/llvm-19/bin
clang: note: diagnostic msg: 
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang: note: diagnostic msg: /tmp/code_2-af78db.c
clang: note: diagnostic msg: /tmp/code_2-af78db.sh
clang: note: diagnostic msg: 

********************

# cat /tmp/code_2-af78db.c
# 1 "&lt;built-in&gt;"
# 1 "code_2.c"
x() { &amp;&amp;e - &amp;&amp;b &lt; x; }



# cat /tmp/code_2-af78db.sh
# Crash reproducer for Ubuntu clang version 19.0.0 (++20240301064251+dd426fa5f931-1~exp1~20240301184412.1845)
# Driver args: "code_2.c" "-O3" "-fsanitize=undefined" "-Wall" "-Wextra" "-pedantic" "-Werror" "-std=c11"
# Original command:  "/usr/lib/llvm-19/bin/clang" "-cc1" "-triple" "x86_64-pc-linux-gnu" "-emit-obj" "-dumpdir" "a-" "-disable-free" "-clear-ast-before-backend" "-disable-llvm-verifier" "-discard-value-names" "-main-file-name" "code_2.c" "-mrelocation-model" "pic" "-pic-level" "2" "-pic-is-pie" "-mframe-pointer=none" "-fmath-errno" "-ffp-contract=on" "-fno-rounding-math" "-mconstructor-aliases" "-funwind-tables=2" "-target-cpu" "x86-64" "-tune-cpu" "generic" "-debugger-tuning=gdb" "-fdebug-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-fcoverage-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-resource-dir" "/usr/lib/llvm-19/lib/clang/19" "-internal-isystem" "/usr/lib/llvm-19/lib/clang/19/include" "-internal-isystem" "/usr/local/include" "-internal-isystem" "/usr/lib/gcc/x86_64-linux-gnu/7/../../../../x86_64-linux-gnu/include" "-internal-externc-isystem" "/usr/include/x86_64-linux-gnu" "-internal-externc-isystem" "/include" "-internal-externc-isystem" "/usr/include" "-O3" "-Wall" "-Wextra" "-Werror" "-pedantic" "-std=c11" "-ferror-limit" "19" "-fsanitize=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound,vptr" "-fsanitize-recover=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,vla-bound,vptr" "-fno-sanitize-memory-param-retval" "-fno-sanitize-address-use-odr-indicator" "-fgnuc-version=4.2.1" "-fskip-odr-check-in-gmf" "-fcolor-diagnostics" "-vectorize-loops" "-vectorize-slp" "-faddrsig" "-D__GCC_HAVE_DWARF2_CFI_ASM=1" "-o" "/tmp/code_2-15394c.o" "-x" "c" "code_2.c"
 "/usr/lib/llvm-19/bin/clang" "-cc1" "-triple" "x86_64-pc-linux-gnu" "-emit-obj" "-dumpdir" "a-" "-disable-free" "-clear-ast-before-backend" "-disable-llvm-verifier" "-discard-value-names" "-main-file-name" "code_2.c" "-mrelocation-model" "pic" "-pic-level" "2" "-pic-is-pie" "-mframe-pointer=none" "-fmath-errno" "-ffp-contract=on" "-fno-rounding-math" "-mconstructor-aliases" "-funwind-tables=2" "-target-cpu" "x86-64" "-tune-cpu" "generic" "-debugger-tuning=gdb" "-fdebug-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-fcoverage-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-O3" "-Wall" "-Wextra" "-Werror" "-pedantic" "-std=c11" "-ferror-limit" "19" "-fsanitize=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound,vptr" "-fsanitize-recover=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,vla-bound,vptr" "-fno-sanitize-memory-param-retval" "-fno-sanitize-address-use-odr-indicator" "-fgnuc-version=4.2.1" "-fskip-odr-check-in-gmf" "-fcolor-diagnostics" "-vectorize-loops" "-vectorize-slp" "-faddrsig" "-D__GCC_HAVE_DWARF2_CFI_ASM=1" "-x" "c" "code_2-af78db.c"

@EugeneZelenko EugeneZelenko added clang:frontend Language frontend issues, e.g. anything involving "Sema" and removed clang Clang issues not falling into any other category labels Jun 13, 2024
@llvmbot
Copy link
Member

llvmbot commented Jun 13, 2024

@llvm/issue-subscribers-clang-frontend

Author: Anonymous (iamanonymouscs)

### Description: Encountered a segmentation fault (core dumped) error while compiling a C code snippet using Clang version 19.0.0 on Ubuntu. The code snippet includes a function definition with a complex expression involving GNU extensions.

Also ICE on trunk, compiler explorer:https:https://godbolt.org/z/sc38GbqW4

OS and Platform:

# uname -a
Linux ubuntu 4.15.0-213-generic #<!-- -->224-Ubuntu SMP Mon Jun 19 13:30:12 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

# clang -v
Ubuntu clang version 19.0.0 (++20240301064251+dd426fa5f931-1~exp1~20240301184412.1845)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/lib/llvm-19/bin
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Candidate multilib: .;@<!-- -->m64
Selected multilib: .;@<!-- -->m64

Program:

# cat code_2.c

x() { &amp;&amp;e - &amp;&amp;b &lt; x; }

Command Lines:

# clang code_2.c -O3 -fsanitize=undefined -Wall -Wextra -pedantic -Werror -std=c11 
code_2.c:1:1: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      | ^
      | int
code_2.c:1:2: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |  ^
      |   void
code_2.c:1:7: error: use of GNU address-of-label extension [-Werror,-Wgnu-label-as-value]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |       ^
code_2.c:1:13: error: use of GNU address-of-label extension [-Werror,-Wgnu-label-as-value]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |             ^
code_2.c:1:11: error: arithmetic on pointers to void is a GNU extension [-Werror,-Wgnu-pointer-arith]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |       ~~~ ^ ~~~
code_2.c:1:17: error: ordered comparison between pointer and integer ('long' and 'int (*)()') [-Werror]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |       ~~~~~~~~~ ^ ~
code_2.c:1:17: error: relational comparison result unused [-Werror,-Wunused-comparison]
    1 | x() { &amp;&amp;e - &amp;&amp;b &lt; x; }
      |       ~~~~~~~~~~^~~
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: /usr/lib/llvm-19/bin/clang -cc1 -triple x86_64-pc-linux-gnu -emit-obj -dumpdir a- -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name code_2.c -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323 -fcoverage-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323 -resource-dir /usr/lib/llvm-19/lib/clang/19 -internal-isystem /usr/lib/llvm-19/lib/clang/19/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wall -Wextra -Werror -pedantic -std=c11 -ferror-limit 19 -fsanitize=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound,vptr -fsanitize-recover=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,vla-bound,vptr -fno-sanitize-memory-param-retval -fno-sanitize-address-use-odr-indicator -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcolor-diagnostics -vectorize-loops -vectorize-slp -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/code_2-15394c.o -x c code_2.c
1.      code_2.c:1:22: current parser token '}'
2.      code_2.c:1:5: parsing function body 'x'
3.      code_2.c:1:5: in compound statement ('{}')
 #<!-- -->0 0x00007fa6de8c5216 llvm::sys::PrintStackTrace(llvm::raw_ostream&amp;, int) (/usr/lib/llvm-19/bin/../lib/libLLVM.so.19.0+0xdc1216)
 #<!-- -->1 0x00007fa6de8c2ec0 llvm::sys::RunSignalHandlers() (/usr/lib/llvm-19/bin/../lib/libLLVM.so.19.0+0xdbeec0)
 #<!-- -->2 0x00007fa6de8c58f0 (/usr/lib/llvm-19/bin/../lib/libLLVM.so.19.0+0xdc18f0)
 #<!-- -->3 0x00007fa6e92b4980 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x12980)
 #<!-- -->4 0x00007fa6e609b05e clang::Decl::getASTContext() const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xe3e05e)
 #<!-- -->5 0x00007fa6e608ae4f clang::NamedDecl::printName(llvm::raw_ostream&amp;) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xe2de4f)
 #<!-- -->6 0x00007fa6e5ee32d6 clang::APValue::printPretty(llvm::raw_ostream&amp;, clang::PrintingPolicy const&amp;, clang::QualType, clang::ASTContext const*) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc862d6)
 #<!-- -->7 0x00007fa6e5ee3bd6 clang::APValue::getAsString[abi:cxx11](clang::ASTContext const&amp;, clang::QualType) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc86bd6)
 #<!-- -->8 0x00007fa6e6178f6d (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xf1bf6d)
 #<!-- -->9 0x00007fa6e6171fe6 (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xf14fe6)
#<!-- -->10 0x00007fa6e611bb07 (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xebeb07)
#<!-- -->11 0x00007fa6e6119420 (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xebc420)
#<!-- -->12 0x00007fa6e611984e clang::Expr::EvaluateForOverflow(clang::ASTContext const&amp;) const (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xebc84e)
#<!-- -->13 0x00007fa6e674c8ec clang::Sema::CheckForIntOverflow(clang::Expr const*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x14ef8ec)
#<!-- -->14 0x00007fa6e674d1f5 clang::Sema::CheckCompletedExpr(clang::Expr*, clang::SourceLocation, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x14f01f5)
#<!-- -->15 0x00007fa6e6abaca6 clang::Sema::ActOnFinishFullExpr(clang::Expr*, clang::SourceLocation, bool, bool, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x185dca6)
#<!-- -->16 0x00007fa6e6ca233a clang::Sema::ActOnExprStmt(clang::ActionResult&lt;clang::Expr*, true&gt;, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x1a4533a)
#<!-- -->17 0x00007fa6e5eb58f6 clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector&lt;clang::Stmt*, 32u&gt;&amp;, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc588f6)
#<!-- -->18 0x00007fa6e5eb52cb clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector&lt;clang::Stmt*, 32u&gt;&amp;, clang::Parser::ParsedStmtContext, clang::SourceLocation*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc582cb)
#<!-- -->19 0x00007fa6e5ebdc80 clang::Parser::ParseCompoundStatementBody(bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc60c80)
#<!-- -->20 0x00007fa6e5ebedef clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&amp;) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc61def)
#<!-- -->21 0x00007fa6e5ed8c36 clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&amp;, clang::Parser::ParsedTemplateInfo const&amp;, clang::Parser::LateParsedAttrList*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7bc36)
#<!-- -->22 0x00007fa6e5e233a7 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&amp;, clang::DeclaratorContext, clang::ParsedAttributes&amp;, clang::Parser::ParsedTemplateInfo&amp;, clang::SourceLocation*, clang::Parser::ForRangeInit*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xbc63a7)
#<!-- -->23 0x00007fa6e5ed7cb4 clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;, clang::ParsingDeclSpec&amp;, clang::AccessSpecifier) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7acb4)
#<!-- -->24 0x00007fa6e5ed769b clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;, clang::ParsingDeclSpec*, clang::AccessSpecifier) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7a69b)
#<!-- -->25 0x00007fa6e5ed68ed clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;, clang::ParsingDeclSpec*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc798ed)
#<!-- -->26 0x00007fa6e5ed4d3c clang::Parser::ParseTopLevelDecl(clang::OpaquePtr&lt;clang::DeclGroupRef&gt;&amp;, clang::Sema::ModuleImportState&amp;) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc77d3c)
#<!-- -->27 0x00007fa6e5ed469f clang::Parser::ParseFirstTopLevelDecl(clang::OpaquePtr&lt;clang::DeclGroupRef&gt;&amp;, clang::Sema::ModuleImportState&amp;) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xc7769f)
#<!-- -->28 0x00007fa6e5e0d006 clang::ParseAST(clang::Sema&amp;, bool, bool) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0xbb0006)
#<!-- -->29 0x00007fa6e7d0a825 clang::FrontendAction::Execute() (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x2aad825)
#<!-- -->30 0x00007fa6e7c860d4 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&amp;) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x2a290d4)
#<!-- -->31 0x00007fa6e7d83f7e clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/usr/lib/llvm-19/bin/../lib/libclang-cpp.so.19.0+0x2b26f7e)
#<!-- -->32 0x000055c9cda4afad cc1_main(llvm::ArrayRef&lt;char const*&gt;, char const*, void*) (/usr/lib/llvm-19/bin/clang+0x12fad)
#<!-- -->33 0x000055c9cda48075 (/usr/lib/llvm-19/bin/clang+0x10075)
#<!-- -->34 0x000055c9cda47213 clang_main(int, char**, llvm::ToolContext const&amp;) (/usr/lib/llvm-19/bin/clang+0xf213)
#<!-- -->35 0x000055c9cda55556 main (/usr/lib/llvm-19/bin/clang+0x1d556)
#<!-- -->36 0x00007fa6dcdf5c87 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21c87)
#<!-- -->37 0x000055c9cda44bfa _start (/usr/lib/llvm-19/bin/clang+0xcbfa)
clang: error: unable to execute command: Segmentation fault (core dumped)
clang: error: clang frontend command failed due to signal (use -v to see invocation)
Ubuntu clang version 19.0.0 (++20240301064251+dd426fa5f931-1~exp1~20240301184412.1845)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/lib/llvm-19/bin
clang: note: diagnostic msg: 
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang: note: diagnostic msg: /tmp/code_2-af78db.c
clang: note: diagnostic msg: /tmp/code_2-af78db.sh
clang: note: diagnostic msg: 

********************

# cat /tmp/code_2-af78db.c
# 1 "&lt;built-in&gt;"
# 1 "code_2.c"
x() { &amp;&amp;e - &amp;&amp;b &lt; x; }



# cat /tmp/code_2-af78db.sh
# Crash reproducer for Ubuntu clang version 19.0.0 (++20240301064251+dd426fa5f931-1~exp1~20240301184412.1845)
# Driver args: "code_2.c" "-O3" "-fsanitize=undefined" "-Wall" "-Wextra" "-pedantic" "-Werror" "-std=c11"
# Original command:  "/usr/lib/llvm-19/bin/clang" "-cc1" "-triple" "x86_64-pc-linux-gnu" "-emit-obj" "-dumpdir" "a-" "-disable-free" "-clear-ast-before-backend" "-disable-llvm-verifier" "-discard-value-names" "-main-file-name" "code_2.c" "-mrelocation-model" "pic" "-pic-level" "2" "-pic-is-pie" "-mframe-pointer=none" "-fmath-errno" "-ffp-contract=on" "-fno-rounding-math" "-mconstructor-aliases" "-funwind-tables=2" "-target-cpu" "x86-64" "-tune-cpu" "generic" "-debugger-tuning=gdb" "-fdebug-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-fcoverage-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-resource-dir" "/usr/lib/llvm-19/lib/clang/19" "-internal-isystem" "/usr/lib/llvm-19/lib/clang/19/include" "-internal-isystem" "/usr/local/include" "-internal-isystem" "/usr/lib/gcc/x86_64-linux-gnu/7/../../../../x86_64-linux-gnu/include" "-internal-externc-isystem" "/usr/include/x86_64-linux-gnu" "-internal-externc-isystem" "/include" "-internal-externc-isystem" "/usr/include" "-O3" "-Wall" "-Wextra" "-Werror" "-pedantic" "-std=c11" "-ferror-limit" "19" "-fsanitize=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound,vptr" "-fsanitize-recover=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,vla-bound,vptr" "-fno-sanitize-memory-param-retval" "-fno-sanitize-address-use-odr-indicator" "-fgnuc-version=4.2.1" "-fskip-odr-check-in-gmf" "-fcolor-diagnostics" "-vectorize-loops" "-vectorize-slp" "-faddrsig" "-D__GCC_HAVE_DWARF2_CFI_ASM=1" "-o" "/tmp/code_2-15394c.o" "-x" "c" "code_2.c"
 "/usr/lib/llvm-19/bin/clang" "-cc1" "-triple" "x86_64-pc-linux-gnu" "-emit-obj" "-dumpdir" "a-" "-disable-free" "-clear-ast-before-backend" "-disable-llvm-verifier" "-discard-value-names" "-main-file-name" "code_2.c" "-mrelocation-model" "pic" "-pic-level" "2" "-pic-is-pie" "-mframe-pointer=none" "-fmath-errno" "-ffp-contract=on" "-fno-rounding-math" "-mconstructor-aliases" "-funwind-tables=2" "-target-cpu" "x86-64" "-tune-cpu" "generic" "-debugger-tuning=gdb" "-fdebug-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-fcoverage-compilation-dir=/root/gdbtest/gcctest/gcc_llvm/llvm/log/closed/HasCode/50323" "-O3" "-Wall" "-Wextra" "-Werror" "-pedantic" "-std=c11" "-ferror-limit" "19" "-fsanitize=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound,vptr" "-fsanitize-recover=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,function,integer-divide-by-zero,nonnull-attribute,null,object-size,pointer-overflow,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,vla-bound,vptr" "-fno-sanitize-memory-param-retval" "-fno-sanitize-address-use-odr-indicator" "-fgnuc-version=4.2.1" "-fskip-odr-check-in-gmf" "-fcolor-diagnostics" "-vectorize-loops" "-vectorize-slp" "-faddrsig" "-D__GCC_HAVE_DWARF2_CFI_ASM=1" "-x" "c" "code_2-af78db.c"

@a-tarasyuk
Copy link
Member

Can I be assigned to this issue?

@a-tarasyuk a-tarasyuk mentioned this issue Jun 13, 2024
Merged
Sirraide pushed a commit that referenced this issue Jun 17, 2024
@a-tarasyuk
[Clang] Disallow non-lvalue values in constant expressions to prevent…
2ebe479 
… invalid pointer offset computation (#95479)

Fixes #95366
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees

@a-tarasyuk a-tarasyuk

Labels
clang:frontend Language frontend issues, e.g. anything involving "Sema" confirmed Verified by a second party constexpr Anything related to constant evaluation crash-on-valid good first issue https://github.com/llvm/llvm-project/contribute
Projects
None yet
Milestone
No milestone
8 participants
@a-tarasyuk @cor3ntin @AaronBallman @EugeneZelenko @iamanonymouscs @tbaederr @llvmbot @zyn0217