Fixup for r165097: build 32-bit ASan compiler-rt library on 64-bit Linux only if just-built clang can build simple 32-bit executables
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@165503 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/runtime/compiler-rt/Makefile b/runtime/compiler-rt/Makefile
index 58cb7fd..0336c01 100644
--- a/runtime/compiler-rt/Makefile
+++ b/runtime/compiler-rt/Makefile
@@ -84,19 +84,35 @@
RuntimeDirs += linux
RuntimeLibrary.linux.Configs :=
+# TryCompile compiler source flags
+# Returns exit code of running a compiler invocation.
+TryCompile = \
+ $(shell \
+ cflags=""; \
+ for flag in $(3); do \
+ cflags="$$cflags $$flag"; \
+ done; \
+ $(1) $$cflags $(2) -o /dev/null > /dev/null 2> /dev/null ; \
+ echo $$?)
+
# We currently only try to generate runtime libraries on x86.
ifeq ($(ARCH),x86)
RuntimeLibrary.linux.Configs += \
full-i386.a profile-i386.a asan-i386.a
endif
+
ifeq ($(ARCH),x86_64)
RuntimeLibrary.linux.Configs += \
full-x86_64.a profile-x86_64.a asan-x86_64.a tsan-x86_64.a
-# We assume that 32-bit ASan library can be built by Clang on 64-bit platform,
-# and add it to the list of runtime libraries so that
-# "clang -faddress-sanitizer -m32" would work.
+# We need to build 32-bit ASan library on 64-bit platform, and add it to the
+# list of runtime libraries to make "clang -faddress-sanitizer -m32" work.
+# We check that Clang can produce working 32-bit binaries by compiling a simple
+# executable.
+test_source = $(LLVM_SRC_ROOT)/tools/clang/runtime/compiler-rt/clang_linux_test_input.c
+ifeq ($(call TryCompile,$(ToolDir)/clang,$(test_source),-m32),0)
RuntimeLibrary.linux.Configs += asan-i386.a
endif
+endif
endif