[libcxx] Add special warning flag detection logic to compiler.py
Summary: Detecting `-Wno-<warning>` flags can be tricky with GCC (See https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html). This patch adds a special `addWarningFlagIfSupported(<flag>)` method to the test compiler object that can be used to add warning flags. The goal of this patch is to help get the test suite running with more warnings.
Reviewers: danalbert, jroelofs
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D11333
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@246069 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/libcxx/compiler.py b/test/libcxx/compiler.py
index 24ac431..4962038 100644
--- a/test/libcxx/compiler.py
+++ b/test/libcxx/compiler.py
@@ -161,3 +161,28 @@
return True
else:
return False
+
+ def addWarningFlagIfSupported(self, flag):
+ """
+ addWarningFlagIfSupported - Add a warning flag if the compiler
+ supports it. Unlike addCompileFlagIfSupported, this function detects
+ when "-Wno-<warning>" flags are unsupported. If flag is a
+ "-Wno-<warning>" GCC will not emit an unknown option diagnostic unless
+ another error is triggered during compilation.
+ """
+ assert isinstance(flag, str)
+ if not flag.startswith('-Wno-'):
+ return self.addCompileFlagIfSupported(flag)
+ flags = ['-Werror', flag]
+ cmd = self.compileCmd('-', os.devnull, flags)
+ # Remove '-v' because it will cause the command line invocation
+ # to be printed as part of the error output.
+ # TODO(EricWF): Are there other flags we need to worry about?
+ if '-v' in cmd:
+ cmd.remove('-v')
+ out, err, rc = lit.util.executeCommand(cmd, input='#error\n')
+ assert rc != 0
+ if flag in err:
+ return False
+ self.compile_flags += [flag]
+ return True
diff --git a/test/libcxx/test/config.py b/test/libcxx/test/config.py
index 502b688..5171f25 100644
--- a/test/libcxx/test/config.py
+++ b/test/libcxx/test/config.py
@@ -574,16 +574,15 @@
'-D_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER',
'-Wall', '-Werror'
]
- self.cxx.addCompileFlagIfSupported('-Wno-attributes')
- if self.cxx.type == 'clang' or self.cxx.type == 'apple-clang':
- self.cxx.addCompileFlagIfSupported('-Wno-pessimizing-move')
- self.cxx.addCompileFlagIfSupported('-Wno-c++11-extensions')
- self.cxx.addCompileFlagIfSupported('-Wno-user-defined-literals')
+ self.cxx.addWarningFlagIfSupported('-Wno-attributes')
+ self.cxx.addWarningFlagIfSupported('-Wno-pessimizing-move')
+ self.cxx.addWarningFlagIfSupported('-Wno-c++11-extensions')
+ self.cxx.addWarningFlagIfSupported('-Wno-user-defined-literals')
std = self.get_lit_conf('std', None)
if std in ['c++98', 'c++03']:
# The '#define static_assert' provided by libc++ in C++03 mode
# causes an unused local typedef whenever it is used.
- self.cxx.addCompileFlagIfSupported('-Wno-unused-local-typedef')
+ self.cxx.addWarningFlagIfSupported('-Wno-unused-local-typedef')
def configure_sanitizer(self):
san = self.get_lit_conf('use_sanitizer', '').strip()
