[Msan] Fix use of mmap(MAP_ANONYMOUS) in the unit tests on FreeBSD

[kutuzov.viktor.84]

Summary

On FreeBSD the 'fd' parameter is required to be (-1) when the MAP_ANONYMOUS flag is specified. Linux ignores that parameter in such cases.

[samsonov]

LGTM

compiler-rt/trunk/lib/msan/tests/msan_test.cc

TEST(MemorySanitizer, shmctl) {
   EXPECT_NOT_POISONED(s_i);
 
   res = shmctl(id, IPC_RMID, 0);
   ASSERT_GT(res, -1);
 }
 
 TEST(MemorySanitizer, shmat) {
   void *p = mmap(NULL, 4096, PROT_READ | PROT_WRITE,
-                 MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
+                 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
   ASSERT_NE(MAP_FAILED, p);
 
   ((char *)p)[10] = *GetPoisoned<U1>();
   ((char *)p)[4095] = *GetPoisoned<U1>();
 
   int res = munmap(p, 4096);
   ASSERT_EQ(0, res);
 
TEST(MemorySanitizer, LargeAllocatorUnpoisonsOnFree) {
   void *p = malloc(1024 * 1024);
   free(p);
 
   typedef void *(*mmap_fn)(void *, size_t, int, int, int, off_t);
   mmap_fn real_mmap = (mmap_fn)dlsym(RTLD_NEXT, "mmap");
 
   // Allocate the page that was released to the OS in free() with the real mmap,
   // bypassing the interceptor.
-  char *q = (char *)real_mmap(p, 4096, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
+  char *q = (char *)real_mmap(p, 4096, PROT_READ | PROT_WRITE,
+                              MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
   ASSERT_NE((char *)0, q);
 
   ASSERT_TRUE(q <= p);
   ASSERT_TRUE(q + 4096 > p);
 
   EXPECT_NOT_POISONED(q[0]);
   EXPECT_NOT_POISONED(q[10]);
   EXPECT_NOT_POISONED(q[100]);