Index: lib/asan/asan_allocator.h
===================================================================
--- lib/asan/asan_allocator.h
+++ lib/asan/asan_allocator.h
@@ -49,11 +49,12 @@
 class AsanChunkView {
  public:
   explicit AsanChunkView(AsanChunk *chunk) : chunk_(chunk) {}
-  bool IsValid();   // Checks if AsanChunkView points to a valid allocated
-                    // or quarantined chunk.
-  uptr Beg();       // First byte of user memory.
-  uptr End();       // Last byte of user memory.
-  uptr UsedSize();  // Size requested by the user.
+  bool IsValid();        // Checks if AsanChunkView points to a valid allocated
+                         // or quarantined chunk.
+  bool IsAllocated();    // Checks if the memory is currently allocated.
+  uptr Beg();            // First byte of user memory.
+  uptr End();            // Last byte of user memory.
+  uptr UsedSize();       // Size requested by the user.
   uptr AllocTid();
   uptr FreeTid();
   bool Eq(const AsanChunkView &c) const { return chunk_ == c.chunk_; }
Index: lib/asan/asan_allocator.cc
===================================================================
--- lib/asan/asan_allocator.cc
+++ lib/asan/asan_allocator.cc
@@ -665,6 +665,9 @@
 bool AsanChunkView::IsValid() {
   return chunk_ && chunk_->chunk_state != CHUNK_AVAILABLE;
 }
+bool AsanChunkView::IsAllocated() {
+  return chunk_ && chunk_->chunk_state == CHUNK_ALLOCATED;
+}
 uptr AsanChunkView::Beg() { return chunk_->Beg(); }
 uptr AsanChunkView::End() { return Beg() + UsedSize(); }
 uptr AsanChunkView::UsedSize() { return chunk_->UsedSize(); }
Index: lib/asan/asan_report.cc
===================================================================
--- lib/asan/asan_report.cc
+++ lib/asan/asan_report.cc
@@ -1012,10 +1012,10 @@
   uptr a2 = reinterpret_cast<uptr>(p2);
   AsanChunkView chunk1 = FindHeapChunkByAddress(a1);
   AsanChunkView chunk2 = FindHeapChunkByAddress(a2);
-  bool valid1 = chunk1.IsValid();
-  bool valid2 = chunk2.IsValid();
-  if ((valid1 != valid2) || (valid1 && valid2 && !chunk1.Eq(chunk2))) {
-    GET_CALLER_PC_BP_SP;                                              \
+  bool valid1 = chunk1.IsAllocated();
+  bool valid2 = chunk2.IsAllocated();
+  if (!valid1 || !valid2 || !chunk1.Eq(chunk2)) {
+    GET_CALLER_PC_BP_SP;
     return ReportInvalidPointerPair(pc, bp, sp, a1, a2);
   }
 }
Index: test/asan/TestCases/invalid-pointer-pairs.cc
===================================================================
--- /dev/null
+++ test/asan/TestCases/invalid-pointer-pairs.cc
@@ -0,0 +1,22 @@
+// RUN: %clangxx_asan -O0 %s -o %t -mllvm -asan-detect-invalid-pointer-pair
+
+// RUN: %env_asan_opts=detect_invalid_pointer_pairs=true not %run %t 2>&1 | FileCheck %s
+
+#include <assert.h>
+#include <stdlib.h>
+
+int main(int argc, char **argv) {
+  assert(argc >= 2);
+  char *p = (char*)malloc(42);
+  char *q = (char*)malloc(42);
+  switch (argv[1][0]) {
+    case 'g':
+      return p > q;
+    case 's':
+      return p - q;
+    case 'f':
+      char *p2 = p+20;
+      free(p);
+      return p == p2;
+  }
+}