Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/compiler-rt/test/msan/alloca.cc

@@ -0,0 +1,25 @@
+// RUN: %clangxx_msan -O0 -g %s -o %t && %run %t
+// RUN: %clangxx_msan -O3 -g %s -o %t && %run %t
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <sanitizer/msan_interface.h>
+
+int main(void) {
+  char *p = (char *)alloca(16);
+  assert(0 == __msan_test_shadow(p, 16));
+  assert(0 == __msan_test_shadow(p + 15, 1));
+
+  memset(p, 0, 16);
+  assert(-1 == __msan_test_shadow(p, 16));
+
+  volatile int x = 0;
+  char * volatile q = (char *)alloca(42 * x);
+  assert(-1 == __msan_test_shadow(p, 16));
+
+  int r[x];
+  int *volatile r2 = r;
+  assert(-1 == __msan_test_shadow(p, 16));
+}