Only use /showIncludes if supported

The auto-configured Windows toolchain now only enables `/showIncludes` if the English language pack for VS is installed and the compiler language can thus be forced to be English. Other languages may use encodings other than ASCII or UTF-8 and thus fail to be recognized by Bazel's `ShowInputFilter`. A warning with a suggested fix is shown if this fails.

See #19451
Fixes #19439

RELNOTES: Compilation actions using the auto-configured MSVC toolchain are forced to emit error messages in English if the English language pack for Visual Studio is installed.

Closes #19497.

PiperOrigin-RevId: 565251294
Change-Id: I926c484c21310ee4d7b5e8d5756cb61e45d6e6ac

src/main/java/com/google/devtools/build/lib/rules/cpp/CppCompileActionBuilder.java

@@ -458,7 +458,9 @@ public boolean useDotdFile(Artifact sourceFile) {
   }
 
   public boolean dotdFilesEnabled() {
-    return cppSemantics.needsDotdInputPruning(configuration) && !shouldParseShowIncludes();
+    return cppSemantics.needsDotdInputPruning(configuration)
+        && !shouldParseShowIncludes()
+        && !featureConfiguration.isEnabled(CppRuleClasses.NO_DOTD_FILE);
   }
 
   public boolean serializedDiagnosticsFilesEnabled() {

src/main/java/com/google/devtools/build/lib/rules/cpp/CppRuleClasses.java

@@ -404,6 +404,9 @@ public static ToolchainTypeRequirement ccToolchainTypeRequirement(RuleDefinition
   /** A string constant for /showIncludes parsing feature, should only be used for MSVC toolchain */
   public static final String PARSE_SHOWINCLUDES = "parse_showincludes";
 
+  /** A string constant for a feature that, if enabled, disables .d file handling. */
+  public static final String NO_DOTD_FILE = "no_dotd_file";
+
   /*
    * A string constant for the fdo_instrument feature.
    */

tools/cpp/BUILD.windows.tpl

@@ -229,6 +229,7 @@ cc_toolchain_config(
     default_link_flags = ["/MACHINE:X64"],
     dbg_mode_debug_flag = "%{dbg_mode_debug_flag_x64}",
     fastbuild_mode_debug_flag = "%{fastbuild_mode_debug_flag_x64}",
+    supports_parse_showincludes = %{msvc_parse_showincludes_x64},
 )
 
 toolchain(
@@ -295,6 +296,7 @@ cc_toolchain_config(
     default_link_flags = ["/MACHINE:X86"],
     dbg_mode_debug_flag = "%{dbg_mode_debug_flag_x86}",
     fastbuild_mode_debug_flag = "%{fastbuild_mode_debug_flag_x86}",
+    supports_parse_showincludes = %{msvc_parse_showincludes_x86},
 )
 
 toolchain(
@@ -361,6 +363,7 @@ cc_toolchain_config(
     default_link_flags = ["/MACHINE:ARM"],
     dbg_mode_debug_flag = "%{dbg_mode_debug_flag_arm}",
     fastbuild_mode_debug_flag = "%{fastbuild_mode_debug_flag_arm}",
+    supports_parse_showincludes = %{msvc_parse_showincludes_arm},
 )
 
 toolchain(
@@ -427,6 +430,7 @@ cc_toolchain_config(
     default_link_flags = ["/MACHINE:ARM64"],
     dbg_mode_debug_flag = "%{dbg_mode_debug_flag_arm64}",
     fastbuild_mode_debug_flag = "%{fastbuild_mode_debug_flag_arm64}",
+    supports_parse_showincludes = %{msvc_parse_showincludes_arm64},
 )
 
 toolchain(
@@ -493,6 +497,7 @@ cc_toolchain_config(
     default_link_flags = ["/MACHINE:X64"],
     dbg_mode_debug_flag = "%{clang_cl_dbg_mode_debug_flag_x64}",
     fastbuild_mode_debug_flag = "%{clang_cl_fastbuild_mode_debug_flag_x64}",
+    supports_parse_showincludes = %{clang_cl_parse_showincludes_x64},
 )
 
 toolchain(
@@ -560,6 +565,7 @@ cc_toolchain_config(
     default_link_flags = ["/MACHINE:ARM64"],
     dbg_mode_debug_flag = "%{clang_cl_dbg_mode_debug_flag_arm64}",
     fastbuild_mode_debug_flag = "%{clang_cl_fastbuild_mode_debug_flag_arm64}",
+    supports_parse_showincludes = %{clang_cl_parse_showincludes_arm64},
 )
 
 toolchain(

tools/cpp/lib_cc_configure.bzl

@@ -148,7 +148,8 @@ def execute(
         repository_ctx,
         command,
         environment = None,
-        expect_failure = False):
+        expect_failure = False,
+        expect_empty_output = False):
     """Execute a command, return stdout if succeed and throw an error if it fails. Doesn't %-escape the result!"""
     if environment:
         result = repository_ctx.execute(command, environment = environment)
@@ -171,10 +172,15 @@ def execute(
                 ),
             )
     stripped_stdout = result.stdout.strip()
-    if not stripped_stdout:
-        auto_configure_fail(
-            "empty output from command %s, stderr: (%s)" % (command, result.stderr),
-        )
+    if expect_empty_output != (not stripped_stdout):
+        if expect_empty_output:
+            auto_configure_fail(
+                "non-empty output from command %s, stdout: (%s), stderr: (%s)" % (command, result.stdout, result.stderr),
+            )
+        else:
+            auto_configure_fail(
+                "empty output from command %s, stderr: (%s)" % (command, result.stderr),
+            )
     return stripped_stdout
 
 def get_cpu_value(repository_ctx):

tools/cpp/windows_cc_configure.bzl

@@ -488,6 +488,28 @@ def _is_support_debug_fastlink(repository_ctx, linker):
     result = execute(repository_ctx, [linker], expect_failure = True)
     return result.find("/DEBUG[:{FASTLINK|FULL|NONE}]") != -1
 
+def _is_support_parse_showincludes(repository_ctx, cl, env):
+    repository_ctx.file(
+        "main.cpp",
+        "#include \"bazel_showincludes.h\"\nint main(){}\n",
+    )
+    repository_ctx.file(
+        "bazel_showincludes.h",
+        "\n",
+    )
+    result = execute(
+        repository_ctx,
+        [cl, "/nologo", "/showIncludes", "/c", "main.cpp", "/out", "main.exe", "/Fo", "main.obj"],
+        # Attempt to force English language. This may fail if the language pack isn't installed.
+        environment = env | {"VSLANG": "1033"},
+    )
+    for file in ["main.cpp", "bazel_showincludes.h", "main.exe", "main.obj"]:
+        execute(repository_ctx, ["cmd", "/C", "del", file], expect_empty_output = True)
+    return any([
+        line.startswith("Note: including file:") and line.endswith("bazel_showincludes.h")
+        for line in result.split("\n")
+    ])
+
 def find_llvm_path(repository_ctx):
     """Find LLVM install path."""
 
@@ -635,6 +657,7 @@ def _get_msvc_vars(repository_ctx, paths, target_arch = "x64", msvc_vars_x64 = N
             "%{msvc_lib_path_" + target_arch + "}": "vc_installation_error_" + target_arch + ".bat",
             "%{dbg_mode_debug_flag_" + target_arch + "}": "/DEBUG",
             "%{fastbuild_mode_debug_flag_" + target_arch + "}": "/DEBUG",
+            "%{msvc_parse_showincludes_" + target_arch + "}": repr(False),
         }
         return msvc_vars
 
@@ -679,6 +702,13 @@ def _get_msvc_vars(repository_ctx, paths, target_arch = "x64", msvc_vars_x64 = N
     support_debug_fastlink = _is_support_debug_fastlink(repository_ctx, build_tools["LINK"])
     write_builtin_include_directory_paths(repository_ctx, "msvc", escaped_cxx_include_directories, file_suffix = "_msvc")
 
+    support_parse_showincludes = _is_support_parse_showincludes(repository_ctx, build_tools["CL"], env)
+    if not support_parse_showincludes:
+        auto_configure_warning("""
+Header pruning has been disabled since Bazel failed to recognize the output of /showIncludes.
+This can result in unnecessary recompilation.
+Fix this by installing the English language pack for the Visual Studio installation at {} and run 'bazel sync --configure'.""".format(vc_path))
+
     msvc_vars = {
         "%{msvc_env_tmp_" + target_arch + "}": escaped_tmp_dir,
         "%{msvc_env_include_" + target_arch + "}": escaped_include_paths,
@@ -689,6 +719,7 @@ def _get_msvc_vars(repository_ctx, paths, target_arch = "x64", msvc_vars_x64 = N
         "%{msvc_ml_path_" + target_arch + "}": build_tools.get("ML", "msvc_arm_toolchain_does_not_support_ml"),
         "%{msvc_link_path_" + target_arch + "}": build_tools["LINK"],
         "%{msvc_lib_path_" + target_arch + "}": build_tools["LIB"],
+        "%{msvc_parse_showincludes_" + target_arch + "}": repr(support_parse_showincludes),
         "%{dbg_mode_debug_flag_" + target_arch + "}": "/DEBUG:FULL" if support_debug_fastlink else "/DEBUG",
         "%{fastbuild_mode_debug_flag_" + target_arch + "}": "/DEBUG:FASTLINK" if support_debug_fastlink else "/DEBUG",
     }
@@ -738,6 +769,7 @@ def _get_clang_cl_vars(repository_ctx, paths, msvc_vars, target_arch):
             "%{clang_cl_dbg_mode_debug_flag_" + target_arch + "}": "/DEBUG",
             "%{clang_cl_fastbuild_mode_debug_flag_" + target_arch + "}": "/DEBUG",
             "%{clang_cl_cxx_builtin_include_directories_" + target_arch + "}": "",
+            "%{clang_cl_parse_showincludes_" + target_arch + "}": repr(False),
         }
         return clang_cl_vars
 
@@ -765,6 +797,8 @@ def _get_clang_cl_vars(repository_ctx, paths, msvc_vars, target_arch):
         # LLVM's lld-link.exe doesn't support /DEBUG:FASTLINK.
         "%{clang_cl_dbg_mode_debug_flag_" + target_arch + "}": "/DEBUG",
         "%{clang_cl_fastbuild_mode_debug_flag_" + target_arch + "}": "/DEBUG",
+        # clang-cl always emits the English language version of the /showIncludes prefix.
+        "%{clang_cl_parse_showincludes_" + target_arch + "}": repr(True),
     }
     return clang_cl_vars
 

tools/cpp/windows_cc_toolchain_config.bzl

@@ -14,6 +14,7 @@
 
 """A Starlark cc_toolchain configuration rule for Windows"""
 
+load("@bazel_tools//tools/build_defs/cc:action_names.bzl", "ACTION_NAMES")
 load(
     "@bazel_tools//tools/cpp:cc_toolchain_config_lib.bzl",
     "action_config",
@@ -28,7 +29,6 @@ load(
     "variable_with_value",
     "with_feature_set",
 )
-load("@bazel_tools//tools/build_defs/cc:action_names.bzl", "ACTION_NAMES")
 
 all_compile_actions = [
     ACTION_NAMES.c_compile,
@@ -187,7 +187,6 @@ def _impl(ctx):
                 "compiler_output_flags",
                 "nologo",
                 "msvc_env",
-                "parse_showincludes",
                 "user_compile_flags",
                 "sysroot",
             ],
@@ -202,7 +201,6 @@ def _impl(ctx):
                 "default_compile_flags",
                 "nologo",
                 "msvc_env",
-                "parse_showincludes",
                 "user_compile_flags",
                 "sysroot",
                 "unfiltered_compile_flags",
@@ -217,7 +215,6 @@ def _impl(ctx):
                 "compiler_output_flags",
                 "nologo",
                 "msvc_env",
-                "parse_showincludes",
                 "user_compile_flags",
                 "sysroot",
             ],
@@ -789,6 +786,7 @@ def _impl(ctx):
 
         parse_showincludes_feature = feature(
             name = "parse_showincludes",
+            enabled = ctx.attr.supports_parse_showincludes,
             flag_sets = [
                 flag_set(
                     actions = [
@@ -802,6 +800,27 @@ def _impl(ctx):
                     flag_groups = [flag_group(flags = ["/showIncludes"])],
                 ),
             ],
+            env_sets = [
+                env_set(
+                    actions = [
+                        ACTION_NAMES.preprocess_assemble,
+                        ACTION_NAMES.c_compile,
+                        ACTION_NAMES.linkstamp_compile,
+                        ACTION_NAMES.cpp_compile,
+                        ACTION_NAMES.cpp_module_compile,
+                        ACTION_NAMES.cpp_header_parsing,
+                    ],
+                    # Force English (and thus a consistent locale) output so that Bazel can parse
+                    # the /showIncludes output without having to guess the encoding.
+                    env_entries = [env_entry(key = "VSLANG", value = "1033")],
+                ),
+            ],
+        )
+
+        # MSVC does not emit .d files.
+        no_dotd_file_feature = feature(
+            name = "no_dotd_file",
+            enabled = True,
         )
 
         treat_warnings_as_errors_feature = feature(
@@ -1101,6 +1120,7 @@ def _impl(ctx):
             external_include_paths_feature,
             preprocessor_defines_feature,
             parse_showincludes_feature,
+            no_dotd_file_feature,
             generate_pdb_file_feature,
             shared_flag_feature,
             linkstamps_feature,
@@ -1417,6 +1437,7 @@ cc_toolchain_config = rule(
         "dbg_mode_debug_flag": attr.string(),
         "fastbuild_mode_debug_flag": attr.string(),
         "tool_bin_path": attr.string(default = "not_found"),
+        "supports_parse_showincludes": attr.bool(),
     },
     provides = [CcToolchainConfigInfo],
 )