mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-10-21 01:05:45 +00:00
b22c76c625
compiler-opts.m4's check for `MOZ_CXX_SUPPORTS_WARNING(-W, unreachable-code-return, ac_cxx_has_wunreachable_code_return)` is broken. The C/C++ code that configure emits for MOZ_CXX_SUPPORTS_WARNING() actually contains a -Wunreachable-code-return warning and, thus, doesn't actually detect that clang supports the -Wunreachable-code-return flag.
This configure code in MOZ_CXX_SUPPORTS_WARNING():
AC_TRY_COMPILE([],
[return(0);],
$3="yes",
$3="no")
generates something like:
int main() {
return(0);
; return 0; }
where the second return, automatically emitted by configure, is unreachable and causes a -Wunreachable-code-return warning.
The fix is to remove the redundant return(0) from MOZ_CXX_SUPPORTS_WARNING(). This allows clang's -Wunreachable-code-return flag to be detected, but then -Wunreachable-code-return breaks other configure checks, including third-party libraries' configure checks (in particular jemalloc) that also have redundant `return(0)`. So all the third-party libraries' configure checks would need to be fixed upstream, which seems like more hassle than the value of the -Wunreachable-code-return warnings.
|
||
|---|---|---|
| .. | ||
| acwinpaths.m4 | ||
| alloc.m4 | ||
| altoptions.m4 | ||
| android.m4 | ||
| arch.m4 | ||
| clang-plugin.m4 | ||
| clean-config.sh | ||
| codeset.m4 | ||
| compiler-opts.m4 | ||
| config.guess | ||
| config.status.m4 | ||
| config.sub | ||
| expandlibs.m4 | ||
| ffi.m4 | ||
| frameptr.m4 | ||
| hooks.m4 | ||
| hotfixes.m4 | ||
| icu.m4 | ||
| install-sh | ||
| ios.m4 | ||
| jemalloc.m4 | ||
| linux.m4 | ||
| lto.m4 | ||
| mozcommonheader.m4 | ||
| mozheader.m4 | ||
| mozprog.m4 | ||
| nspr-build.m4 | ||
| nspr.m4 | ||
| nss.m4 | ||
| pkg.m4 | ||
| rust.m4 | ||
| subconfigure.m4 | ||
| toolchain.m4 | ||
| winsdk.m4 | ||
| wrapper.m4 | ||
| zlib.m4 | ||