From 8b7f6f5a5b17117e9da8c1497937da80ea72e5b9 Mon Sep 17 00:00:00 2001
From: Lucian Grijincu <lucian@fb.com>
Date: Mon, 1 Feb 2016 17:00:24 -0800
Subject: [PATCH] folly: #define UNDEFINED_SANITIZER in ubsan mode
Summary:
Undefined Sanitizer doesn't define any macro to detect that it's active.
The build system should provide `-DUNDEFINED_SANITIZER` when building
with -fsanitize=undefined or any of the other flags from
http://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html
FWIW: Chrome defines the same preprocessor symbol:
https://chromium.googlesource.com/chromium/src/+/ac18f489dca8c902e4dfaa1a28d716b7914121d0%5E%21/build/common.gypi
Reviewed By: andrewjcg
Differential Revision: D2885167
fb-gh-sync-id: e1129c0863bfde5d032c32e7d5cea7c43d82009f
---
folly/CPortability.h | 19 ++++++++++++++++++-
folly/test/MemcpyTest.cpp | 4 +++-
2 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/folly/CPortability.h b/folly/CPortability.h
index e5099d23..c348b361 100644
--- a/folly/CPortability.h
+++ b/folly/CPortability.h
@@ -56,4 +56,21 @@
# define FOLLY_DISABLE_ADDRESS_SANITIZER
#endif
-#endif
+
+/**
+ * ASAN/MSAN/TSAN define pre-processor symbols:
+ * ADDRESS_SANITIZER/MEMORY_SANITIZER/THREAD_SANITIZER.
+ *
+ * UBSAN doesn't define anything and makes it hard to
+ * conditionally compile.
+ *
+ * The build system should define UNDEFINED_SANITIZER=1 when UBSAN is
+ * used as folly whitelists some functions.
+ */
+#if UNDEFINED_SANITIZER
+# define UBSAN_DISABLE(x) __attribute__((no_sanitize(x)))
+#else
+# define UBSAN_DISABLE(x)
+#endif // UNDEFINED_SANITIZER
+
+#endif // CPORTABILITY_H
diff --git a/folly/test/MemcpyTest.cpp b/folly/test/MemcpyTest.cpp
index badd3447..73b64ca1 100644
--- a/folly/test/MemcpyTest.cpp
+++ b/folly/test/MemcpyTest.cpp
@@ -14,6 +14,8 @@
* limitations under the License.
*/
+#include <folly/Portability.h>
+
#include <gtest/gtest.h>
namespace {
@@ -30,7 +32,7 @@ void init() {
}
}
-TEST(memcpy, zero_len) {
+TEST(memcpy, zero_len) UBSAN_DISABLE("nonnull-attribute") {
// If length is 0, we shouldn't touch any memory. So this should
// not crash.
char* srcNull = nullptr;
--
2.34.1