Merge "Enable object-size sanitizer for C++" into main am: 411346c919

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/3259736

Change-Id: I36e74219c08a32bb5a3a4076fb8b86a9c5c421bd
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

android/config.go

@@ -238,6 +238,11 @@ func (c Config) ReleaseAconfigFlagDefaultPermission() string {
 	return c.config.productVariables.ReleaseAconfigFlagDefaultPermission
 }
 
+// Enable object size sanitizer
+func (c Config) ReleaseBuildObjectSizeSanitizer() bool {
+	return c.config.productVariables.GetBuildFlagBool("RELEASE_BUILD_OBJECT_SIZE_SANITIZER")
+}
+
 // The flag indicating behavior for the tree wrt building modules or using prebuilts
 // derived from RELEASE_DEFAULT_MODULE_BUILD_FROM_SOURCE
 func (c Config) ReleaseDefaultModuleBuildFromSource() bool {

cc/sanitize.go

@@ -1437,11 +1437,11 @@ func sanitizerRuntimeMutator(mctx android.BottomUpMutatorContext) {
 					//"null",
 					//"shift-base",
 					//"signed-integer-overflow",
-					// TODO(danalbert): Fix UB in libc++'s __tree so we can turn this on.
-					// https://llvm.org/PR19302
-					// http://reviews.llvm.org/D6974
-					// "object-size",
 				)
+
+				if mctx.Config().ReleaseBuildObjectSizeSanitizer() {
+					sanitizers = append(sanitizers, "object-size")
+				}
 			}
 			sanitizers = append(sanitizers, sanProps.Misc_undefined...)
 		}