[compiler-rt] r293992 - [sanitizer] Fix 'dyld: Symbol not found: _memmem' linkage error on Darwin 10.6

[Maxim Ostapenko via llvm-commits]

Author: chefmax
Date: Fri Feb  3 00:58:14 2017
New Revision: 293992

URL: http://llvm.org/viewvc/llvm-project?rev=293992&view=rev
Log:
[sanitizer] Fix 'dyld: Symbol not found: _memmem' linkage error on Darwin 10.6

This patch tries to fixes sanitizer linkage errors on Darwin 10.6 originally reporded
in GCC's pr78663 (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78663).

Differential Revision: https://reviews.llvm.org/D29287

Modified:
    compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc
    compiler-rt/trunk/lib/sanitizer_common/sanitizer_platform_interceptors.h

Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc?rev=293992&r1=293991&r2=293992&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_mac.cc Fri Feb  3 00:58:14 2017
@@ -93,20 +93,22 @@ namespace __sanitizer {
 
 #include "sanitizer_syscall_generic.inc"
 
-// Direct syscalls, don't call libmalloc hooks.
+// Direct syscalls, don't call libmalloc hooks (but not available on 10.6).
 extern "C" void *__mmap(void *addr, size_t len, int prot, int flags, int fildes,
-                        off_t off);
-extern "C" int __munmap(void *, size_t);
+                        off_t off) SANITIZER_WEAK_ATTRIBUTE;
+extern "C" int __munmap(void *, size_t) SANITIZER_WEAK_ATTRIBUTE;
 
 // ---------------------- sanitizer_libc.h
 uptr internal_mmap(void *addr, size_t length, int prot, int flags,
                    int fd, u64 offset) {
   if (fd == -1) fd = VM_MAKE_TAG(VM_MEMORY_ANALYSIS_TOOL);
-  return (uptr)__mmap(addr, length, prot, flags, fd, offset);
+  if (__mmap) return (uptr)__mmap(addr, length, prot, flags, fd, offset);
+  return (uptr)mmap(addr, length, prot, flags, fd, offset);
 }
 
 uptr internal_munmap(void *addr, uptr length) {
-  return __munmap(addr, length);
+  if (__munmap) return __munmap(addr, length);
+  return munmap(addr, length);
 }
 
 int internal_mprotect(void *addr, uptr length, int prot) {
@@ -192,17 +194,19 @@ uptr internal_sigprocmask(int how, __san
   return sigprocmask(how, set, oldset);
 }
 
-// Doesn't call pthread_atfork() handlers.
-extern "C" pid_t __fork(void);
+// Doesn't call pthread_atfork() handlers (but not available on 10.6).
+extern "C" pid_t __fork(void) SANITIZER_WEAK_ATTRIBUTE;
 
 int internal_fork() {
-  return __fork();
+  if (__fork)
+    return __fork();
+  return fork();
 }
 
 int internal_forkpty(int *amaster) {
   int master, slave;
   if (openpty(&master, &slave, nullptr, nullptr, nullptr) == -1) return -1;
-  int pid = __fork();
+  int pid = internal_fork();
   if (pid == -1) {
     close(master);
     close(slave);

Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_platform_interceptors.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_platform_interceptors.h?rev=293992&r1=293991&r2=293992&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_platform_interceptors.h (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_platform_interceptors.h Fri Feb  3 00:58:14 2017
@@ -83,8 +83,16 @@
 #define SANITIZER_INTERCEPT_MEMMOVE 1
 #define SANITIZER_INTERCEPT_MEMCPY 1
 #define SANITIZER_INTERCEPT_MEMCMP 1
+#if defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \
+    __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 1070
+# define SI_MAC_DEPLOYMENT_BELOW_10_7 1
+#else
+# define SI_MAC_DEPLOYMENT_BELOW_10_7 0
+#endif
+// memmem on Darwin doesn't exist on 10.6
 // FIXME: enable memmem on Windows.
-#define SANITIZER_INTERCEPT_MEMMEM SI_NOT_WINDOWS
+#define SANITIZER_INTERCEPT_MEMMEM \
+  SI_NOT_WINDOWS && !SI_MAC_DEPLOYMENT_BELOW_10_7
 #define SANITIZER_INTERCEPT_MEMCHR 1
 #define SANITIZER_INTERCEPT_MEMRCHR SI_FREEBSD || SI_LINUX