When building a distributed compiler on Linux where we use ThinLTO to
create the LLVM shared object this commit switches the compiler to
dynamically linking that LLVM artifact instead of statically linking to
LLVM. The primary goal here is to reduce CI compile times, avoiding two+
ThinLTO builds of all of LLVM. By linking dynamically to LLVM we'll
reuse the one ThinLTO step done by LLVM's build itself.

Lots of discussion about this change can be found [here] and down. A
perf run will show whether this is worth it or not!

[here]: rust-lang#53245 (comment)

…orms

This reverts commit 1346619.

…inters

This commit moves jemalloc to just the rustc binary rather than the
rustc_driver shared library, enusring that it's only used for binaries
that opt-in to it like rustc rather than other binaries using
librustc_driver like rustdoc/rls/etc. This will hopefully address rust-lang#56980

I was assuming that rust-lang#56792 would
have resulted in compiletest tests being executed in CI. However, I
couldn't find any mentions of the unit test names in any CI logs.

This adds the compiletest test execution to the checktools.sh script.

This way, checktools.sh continues to be used only for tools that are
published later on.

Instead disable creation of assumptions during inlining using an
LLVM opt flag.

The -Z arg-align-attributes option which previously controlled this
behavior is removed.

…x-sparc64

This is in accordance with the SPARC Compliance Definition 2.4.1,
Page 3P-12. It says that structs of up to 8 bytes (which applies
to empty structs as well) are to be passed in one register.

box: Add documentation for `From` impls

This is a part of rust-lang#51430. A brief description of the behaviour and examples are added to the documentation.

I am not sure what sort of examples to put for the `From` for `Pin` as my [code](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2015&gist=97c908f44e41c9faeffec5b61d72a03e) doesn't even manage to compile using the nightly build.

Somehow I feel that I missed out something so do let me know if more information is needed in the documentation or any of the examples require change.

…k, r=Centril

Add missing link in docs

r? @steveklabnik

…oerister

bootstrap: Link LLVM as a dylib with ThinLTO

When building a distributed compiler on Linux where we use ThinLTO to
create the LLVM shared object this commit switches the compiler to
dynamically linking that LLVM artifact instead of statically linking to
LLVM. The primary goal here is to reduce CI compile times, avoiding two+
ThinLTO builds of all of LLVM. By linking dynamically to LLVM we'll
reuse the one ThinLTO step done by LLVM's build itself.

Lots of discussion about this change can be found [here] and down. A
perf run will show whether this is worth it or not!

[here]: rust-lang#53245 (comment)

Add `std::os::fortanix_sgx` module

This PR adds the `std::os::sgx` module to expose platform-specific APIs behind the `sgx_platform` feature gate.

Depends on rust-lang#56972 to be able to meaningfully build `std::os` documentation for non-standard targets.

Tracking issue: rust-lang#56975

Allow testing pointers for inboundedness while forbidding dangling pointers

r? @RalfJung

…Simulacrum

rustc: Move jemalloc from rustc_driver to rustc

This commit moves jemalloc to just the rustc binary rather than the
rustc_driver shared library, enusring that it's only used for binaries
that opt-in to it like rustc rather than other binaries using
librustc_driver like rustdoc/rls/etc. This will hopefully address rust-lang#56980

…, r=kennytm

Actually run compiletest tests on CI

I was assuming that rust-lang#56792 would
have resulted in compiletest tests being executed on CI. However, I
couldn't find any mentions of the unit test names in any CI logs.

This adds the compiletest test execution to the checktools.sh script.

Enable emission of alignment attrs for pointer params

Instead disable creation of assumptions during inlining using an LLVM opt flag. For non-inlined functions, this gives us alignment information, while not inserting any assumes that kill other optimizations.

The `-Z arg-align-attributes` option which previously controlled this behavior is removed.

Fixes rust-lang#54982.

r? @nagisa

cc @eddyb who added the current behavior, and @scottmcm, who added the `-Z arg-align-attributes` flag.

Fix recursion limits

r? @michaelwoerister

librustc_codegen_llvm: Don't eliminate empty structs in C ABI on linux-sparc64

This is in accordance with the SPARC Compliance Definition 2.4.1,
Page 3P-12. It says that structs of up to 8 bytes (which applies
to empty structs as well) are to be passed in one register.