1 files changed, 21 insertions, 0 deletions
diff --git a/compiler-rt/test/msan/realloc-origin.cpp b/compiler-rt/test/msan/realloc-origin.cpp
new file mode 100644
index 00000000000..5bceddad660
--- /dev/null
+++ b/compiler-rt/test/msan/realloc-origin.cpp
@@ -0,0 +1,21 @@
+// RUN: %clangxx_msan -fsanitize-memory-track-origins -O0 %s -o %t && not %run %t >%t.out 2>&1
+// RUN: FileCheck %s < %t.out
+// RUN: %clangxx_msan -fsanitize-memory-track-origins -O2 %s -o %t && not %run %t >%t.out 2>&1
+// RUN: FileCheck %s < %t.out
+
+// This test relies on realloc from 100 to 101 being done in-place.
+
+#include <stdlib.h>
+int main(int argc, char **argv) {
+  char *p = (char *)malloc(100);
+  p = (char *)realloc(p, 101);
+  char x = p[100];
+  free(p);
+  return x;
+  // CHECK: WARNING: MemorySanitizer: use-of-uninitialized-value
+  // CHECK: {{#0 0x.* in main .*realloc-origin.cpp:}}[[@LINE-2]]
+
+  // CHECK: Uninitialized value was created by a heap allocation
+  // CHECK: {{#0 0x.* in .*realloc}}
+  // CHECK: {{#1 0x.* in main .*realloc-origin.cpp:}}[[@LINE-9]]
+}