[compiler-rt][SystemZ] Work around ASAN failures via -fno-partial-inlining

Since updating the SystemZ LLVM build bot system to Ubuntu 18.04, all bots
are red due to two ASAN failures.  It turns out these are triggered due to
building the ASAN support libraries, in particular the interceptor routines
using GCC 7.  Specifically, at least on our platform, this compiler decides
to "partially inline" some of those interceptors, creating intermediate
stub routines like "__interceptor_recvfrom.part.321".  These will show up
in the backtraces at interception points, causing testsuite failures.

As a workaround to get the build bots green again, this patch adds the
-fno-partial-inlining command line option when building the common
sanitizer support libraries on s390x, if that option is supported by
the compiler.

llvm-svn: 363679

compiler-rt/CMakeLists.txt

@@ -288,6 +288,15 @@ if(DEFINED TARGET_powerpc64le_CFLAGS)
   append_list_if(COMPILER_RT_HAS_FNO_FUNCTION_SECTIONS_FLAG -fno-function-sections TARGET_powerpc64le_CFLAGS)
 endif()
 
+# The following is a workaround for s390x.  This avoids creation of "partial
+# inline" function fragments when building the asan libraries with certain
+# GCC versions.  The presence of those fragments, in particular for the
+# interceptors, changes backtraces seen in asan error cases, which causes
+# testsuite failures.
+if("${COMPILER_RT_DEFAULT_TARGET_ARCH}" MATCHES "s390x")
+  append_list_if(COMPILER_RT_HAS_FNO_PARTIAL_INLINING_FLAG -fno-partial-inlining SANITIZER_COMMON_CFLAGS)
+endif()
+
 if(MSVC)
   # Replace the /M[DT][d] flags with /MT, and strip any definitions of _DEBUG,
   # which cause definition mismatches at link time.

compiler-rt/cmake/config-ix.cmake

@@ -74,6 +74,7 @@ check_cxx_compiler_flag("-Werror -msse3" COMPILER_RT_HAS_MSSE3_FLAG)
 check_cxx_compiler_flag("-Werror -msse4.2"   COMPILER_RT_HAS_MSSE4_2_FLAG)
 check_cxx_compiler_flag(--sysroot=.          COMPILER_RT_HAS_SYSROOT_FLAG)
 check_cxx_compiler_flag("-Werror -mcrc"      COMPILER_RT_HAS_MCRC_FLAG)
+check_cxx_compiler_flag(-fno-partial-inlining COMPILER_RT_HAS_FNO_PARTIAL_INLINING_FLAG)
 
 if(NOT WIN32 AND NOT CYGWIN)
   # MinGW warns if -fvisibility-inlines-hidden is used.