Fix broken flag existence check for linking flags in unix_cc_configure.
Fixes #5090
RELNOTES: NONE.
PiperOrigin-RevId: 198870918
diff --git a/tools/cpp/unix_cc_configure.bzl b/tools/cpp/unix_cc_configure.bzl
index 82cb60d..3141b0b 100644
--- a/tools/cpp/unix_cc_configure.bzl
+++ b/tools/cpp/unix_cc_configure.bzl
@@ -150,7 +150,7 @@
for p in inc_dirs.split("\n")
]
-def _is_option_supported(repository_ctx, cc, option):
+def _is_compiler_option_supported(repository_ctx, cc, option):
"""Checks that `option` is supported by the C compiler. Doesn't %-escape the option."""
result = repository_ctx.execute([
cc,
@@ -162,9 +162,16 @@
])
return result.stderr.find(option) == -1
-def _add_option_if_supported(repository_ctx, cc, option):
- """Returns `[option]` if supported, `[]` otherwise. Doesn't %-escape the option."""
- return [option] if _is_option_supported(repository_ctx, cc, option) else []
+def _is_linker_option_supported(repository_ctx, cc, option):
+ """Checks that `option` is supported by the C compiler. Doesn't %-escape the option."""
+ result = repository_ctx.execute([
+ cc,
+ option,
+ "-o",
+ "/dev/null",
+ str(repository_ctx.path("tools/cpp/empty.cc")),
+ ])
+ return result.stderr.find(option) == -1
def _is_gold_supported(repository_ctx, cc):
"""Checks that `gold` is supported by the C compiler."""
@@ -182,6 +189,14 @@
])
return result.return_code == 0
+def _add_compiler_option_if_supported(repository_ctx, cc, option):
+ """Returns `[option]` if supported, `[]` otherwise. Doesn't %-escape the option."""
+ return [option] if _is_compiler_option_supported(repository_ctx, cc, option) else []
+
+def _add_linker_option_if_supported(repository_ctx, cc, option):
+ """Returns `[option]` if supported, `[]` otherwise. Doesn't %-escape the option."""
+ return [option] if _is_linker_option_supported(repository_ctx, cc, option) else []
+
def _get_no_canonical_prefixes_opt(repository_ctx, cc):
# If the compiler sometimes rewrites paths in the .d files without symlinks
# (ie when they're shorter), it confuses Bazel's logic for verifying all
@@ -190,13 +205,13 @@
# The '-fno-canonical-system-headers' should be enough, but clang does not
# support it, so we also try '-no-canonical-prefixes' if first option does
# not work.
- opt = _add_option_if_supported(
+ opt = _add_compiler_option_if_supported(
repository_ctx,
cc,
"-fno-canonical-system-headers",
)
if len(opt) == 0:
- return _add_option_if_supported(
+ return _add_compiler_option_if_supported(
repository_ctx,
cc,
"-no-canonical-prefixes",
@@ -251,11 +266,11 @@
] + _escaped_cplus_include_paths(repository_ctx),
"linker_flag": (
["-fuse-ld=gold"] if supports_gold_linker else []
- ) + _add_option_if_supported(
+ ) + _add_linker_option_if_supported(
repository_ctx,
cc,
"-Wl,-no-as-needed",
- ) + _add_option_if_supported(
+ ) + _add_linker_option_if_supported(
repository_ctx,
cc,
"-Wl,-z,relro,-z,now",
@@ -270,7 +285,7 @@
# Gold linker only? Can we enable this by default?
# "-Wl,--warn-execstack",
# "-Wl,--detect-odr-violations"
- ] + _add_option_if_supported(
+ ] + _add_compiler_option_if_supported(
# Have gcc return the exit code from ld.
repository_ctx,
cc,
@@ -298,24 +313,27 @@
# All warnings are enabled. Maybe enable -Werror as well?
"-Wall",
# Enable a few more warnings that aren't part of -Wall.
- ] + (["-Wthread-safety", "-Wself-assign"] if darwin else bin_search_flag + [
+ ] + ((
+ _add_compiler_option_if_supported(repository_ctx, cc, "-Wthread-safety") +
+ _add_compiler_option_if_supported(repository_ctx, cc, "-Wself-assign")
+ ) if darwin else bin_search_flag + [
# Always have -B/usr/bin, see https://github.com/bazelbuild/bazel/issues/760.
"-B/usr/bin",
]) + (
# Disable problematic warnings.
- _add_option_if_supported(repository_ctx, cc, "-Wunused-but-set-parameter") +
+ _add_compiler_option_if_supported(repository_ctx, cc, "-Wunused-but-set-parameter") +
# has false positives
- _add_option_if_supported(repository_ctx, cc, "-Wno-free-nonheap-object") +
+ _add_compiler_option_if_supported(repository_ctx, cc, "-Wno-free-nonheap-object") +
# Enable coloring even if there's no attached terminal. Bazel removes the
# escape sequences if --nocolor is specified.
- _add_option_if_supported(repository_ctx, cc, "-fcolor-diagnostics")
+ _add_compiler_option_if_supported(repository_ctx, cc, "-fcolor-diagnostics")
) + [
# Keep stack frames for debugging, even in opt mode.
"-fno-omit-frame-pointer",
],
}
-def _opt_content(darwin):
+def _opt_content(repository_ctx, cc, darwin):
"""Return the content of the opt specific section of the CROSSTOOL file."""
return {
"compiler_flag": [
@@ -341,7 +359,9 @@
"-ffunction-sections",
"-fdata-sections",
],
- "linker_flag": [] if darwin else ["-Wl,--gc-sections"],
+ "linker_flag": (
+ [] if darwin else _add_linker_option_if_supported(repository_ctx, cc, "-Wl,--gc-sections")
+ ),
}
def _dbg_content():
@@ -470,7 +490,7 @@
tool_paths = _get_tool_paths(repository_ctx, overriden_tools)
crosstool_content = _crosstool_content(repository_ctx, cc, cpu_value, darwin)
- opt_content = _opt_content(darwin)
+ opt_content = _opt_content(repository_ctx, cc, darwin)
dbg_content = _dbg_content()
repository_ctx.template(
