commit eb8db9d65f4112b05af1df0bca82b35d2aa7d17e
author James Zern <jzern@google.com> Wed Aug 17 19:20:25 2022 -0700
committer James Zern <jzern@google.com> Fri Sep 02 18:47:46 2022 +0000
tree 2ac91335d8d95a184d400344bd4aa5ea60546038
parent 74c221a3570f89a02d6f068b1a3692fb04e5abad

md5_utils.c: add AOM_NO_UNSIGNED_SHIFT_CHECK

and use it on MD5Transform(); this behavior is well defined and is only
a warning with -fsanitize=integer, not -fsanitize=undefined.

quiets warnings of the form:
md5_utils.c:163:3: runtime error: left shift of 143704723 by 7 places
cannot be represented in type 'unsigned int'

Bug: aomedia:3136
Bug: b/229626362
Change-Id: I60a384b2c2556f5ce71ad8ebce050329aba0b4e4

common/md5_utils.c

diff --git a/common/md5_utils.c b/common/md5_utils.c
index b69e1cc..c69aa57 100644
--- a/common/md5_utils.c
+++ b/common/md5_utils.c
@@ -150,19 +150,26 @@
 #define AOM_NO_UNSIGNED_OVERFLOW_CHECK \
   __attribute__((no_sanitize("unsigned-integer-overflow")))
 #endif
-#endif
+#if __clang_major__ >= 12
+#define VPX_NO_UNSIGNED_SHIFT_CHECK \
+  __attribute__((no_sanitize("unsigned-shift-base")))
+#endif  // __clang__ >= 12
+#endif  // __clang__
 
 #ifndef AOM_NO_UNSIGNED_OVERFLOW_CHECK
 #define AOM_NO_UNSIGNED_OVERFLOW_CHECK
 #endif
+#ifndef AOM_NO_UNSIGNED_SHIFT_CHECK
+#define AOM_NO_UNSIGNED_SHIFT_CHECK
+#endif
 
 /*
  * The core of the MD5 algorithm, this alters an existing MD5 hash to
  * reflect the addition of 16 longwords of new data.  MD5Update blocks
  * the data and converts bytes into longwords for this routine.
  */
-AOM_NO_UNSIGNED_OVERFLOW_CHECK void MD5Transform(UWORD32 buf[4],
-                                                 UWORD32 const in[16]) {
+AOM_NO_UNSIGNED_OVERFLOW_CHECK AOM_NO_UNSIGNED_SHIFT_CHECK void MD5Transform(
+    UWORD32 buf[4], UWORD32 const in[16]) {
   register UWORD32 a, b, c, d;
 
   a = buf[0];
@@ -245,5 +252,6 @@
 }
 
 #undef AOM_NO_UNSIGNED_OVERFLOW_CHECK
+#undef AOM_NO_UNSIGNED_SHIFT_CHECK
 
 #endif