Bug 1274334 - Enable STL wrappers on macos. r=firefox-build-system-reviewers,ahochheiden

Practically speaking, this doesn't make a huge difference, because
libmozglue contains operator new/operator delete overrides. This will
enable inlining opportunities, though.

It is worth noting that there's equivalent code in
js/src/old-configure.in but it's left as is because it is actually no-op
at the moment. This will be fixed in bug 1829049.

The check for __EXCEPTIONS is replaced with __cpp_exceptions because the
former is defined for any type of exception, including ObjC exceptions,
while the latter is defined for C++ exceptions only.

Differential Revision: https://phabricator.services.mozilla.com/D175976

config/gcc-stl-wrapper.template.h

@@ -8,9 +8,7 @@
 #ifndef mozilla_${HEADER}_h
 #define mozilla_${HEADER}_h
 
-// For some reason, Apple's GCC refuses to honor -fno-exceptions when
-// compiling ObjC.
-#if defined(__EXCEPTIONS) && __EXCEPTIONS && !(__OBJC__ && __GNUC__ && XP_IOS)
+#if defined(__cpp_exceptions) && __cpp_exceptions
 #  error "STL code can only be used with -fno-exceptions"
 #endif
 

old-configure.in

@@ -597,14 +597,8 @@ MOZ_CXX11
 
 AC_LANG_C
 
-case "${OS_TARGET}" in
-Darwin)
-  ;;
-*)
-  STL_FLAGS="-I${DIST}/stl_wrappers"
-  WRAP_STL_INCLUDES=1
-  ;;
-esac
+STL_FLAGS="-I${DIST}/stl_wrappers"
+WRAP_STL_INCLUDES=1
 
 if test "$MOZ_BUILD_APP" = "tools/crashreporter/injector"; then
     WRAP_STL_INCLUDES=

xpcom/tests/gtest/TestSTLWrappers.cpp

@@ -47,13 +47,19 @@ void ShouldAbort() {
   fputs("TEST-FAIL | TestSTLWrappers.cpp | didn't abort()?\n", stderr);
 }
 
-#ifdef XP_WIN
+#if defined(XP_WIN) || (defined(XP_MACOSX) && !defined(MOZ_DEBUG))
 TEST(STLWrapper, DISABLED_ShouldAbortDeathTest)
 #else
 TEST(STLWrapper, ShouldAbortDeathTest)
 #endif
 {
   ASSERT_DEATH_IF_SUPPORTED(ShouldAbort(),
+#ifdef __GLIBCXX__
+                            // Only libstdc++ will print this message.
                             "terminate called after throwing an instance of "
-                            "'std::out_of_range'|vector::_M_range_check");
+                            "'std::out_of_range'|vector::_M_range_check"
+#else
+                            ""
+#endif
+  );
 }