[ASan] Allow ASan default runtime options be overriden at compile time by providing ASAN_DEFAULT_OPTIONS macro

llvm-svn: 175512

2 files changed, 19 insertions, 3 deletions

diff --git a/compiler-rt/lib/asan/asan_flags.h b/compiler-rt/lib/asan/asan_flags.h
index 6c4e362..47c14aa 100644
--- a/compiler-rt/lib/asan/asan_flags.h
+++ b/compiler-rt/lib/asan/asan_flags.h
@@ -17,11 +17,13 @@
 
 #include "sanitizer_common/sanitizer_internal_defs.h"
 
-// ASan flag values can be defined in three ways:
+// ASan flag values can be defined in four ways:
 // 1) initialized with default values at startup.
-// 2) overriden from string returned by user-specified function
+// 2) overriden during compilation of ASan runtime by providing
+//    compile definition ASAN_DEFAULT_OPTIONS.
+// 3) overriden from string returned by user-specified function
 //    __asan_default_options().
-// 3) overriden from env variable ASAN_OPTIONS.
+// 4) overriden from env variable ASAN_OPTIONS.
 
 namespace __asan {
 
diff --git a/compiler-rt/lib/asan/asan_rtl.cc b/compiler-rt/lib/asan/asan_rtl.cc
index 2f170fa..39b722a 100644
--- a/compiler-rt/lib/asan/asan_rtl.cc
+++ b/compiler-rt/lib/asan/asan_rtl.cc
@@ -76,6 +76,17 @@ static const char *MaybeCallAsanDefaultOptions() {
   return (&__asan_default_options) ? __asan_default_options() : "";
 }
 
+static const char *MaybeUseAsanDefaultOptionsCompileDefiniton() {
+#ifdef ASAN_DEFAULT_OPTIONS
+// Stringize the macro value.
+# define ASAN_STRINGIZE(x) #x
+# define ASAN_STRINGIZE_OPTIONS(options) ASAN_STRINGIZE(options)
+  return ASAN_STRINGIZE_OPTIONS(ASAN_DEFAULT_OPTIONS);
+#else
+  return "";
+#endif
+}
+
 static void ParseFlagsFromString(Flags *f, const char *str) {
   ParseFlag(str, &f->quarantine_size, "quarantine_size");
   ParseFlag(str, &f->symbolize, "symbolize");
@@ -156,6 +167,9 @@ void InitializeFlags(Flags *f, const char *env) {
   f->alloc_dealloc_mismatch = true;
   f->use_stack_depot = true;  // Only affects allocator2.
 
+  // Override from compile definition.
+  ParseFlagsFromString(f, MaybeUseAsanDefaultOptionsCompileDefiniton());
+
   // Override from user-specified string.
   ParseFlagsFromString(f, MaybeCallAsanDefaultOptions());
   if (flags()->verbosity) {