3 files changed, 15 insertions, 2 deletions
diff --git a/compiler-rt/lib/asan/asan_poisoning.cc b/compiler-rt/lib/asan/asan_poisoning.cc
index c3a82aa0049..62cbfe6f024 100644
--- a/compiler-rt/lib/asan/asan_poisoning.cc
+++ b/compiler-rt/lib/asan/asan_poisoning.cc
@@ -32,7 +32,7 @@ bool CanPoisonMemory() {
 }
 
 void PoisonShadow(uptr addr, uptr size, u8 value) {
-  if (!CanPoisonMemory()) return;
+  if (value && !CanPoisonMemory()) return;
   CHECK(AddrIsAlignedByGranularity(addr));
   CHECK(AddrIsInMem(addr));
   CHECK(AddrIsAlignedByGranularity(addr + size));
diff --git a/compiler-rt/lib/asan/asan_poisoning.h b/compiler-rt/lib/asan/asan_poisoning.h
index 1e00070bcf6..42cdc850ecc 100644
--- a/compiler-rt/lib/asan/asan_poisoning.h
+++ b/compiler-rt/lib/asan/asan_poisoning.h
@@ -38,7 +38,7 @@ void PoisonShadowPartialRightRedzone(uptr addr,
 // performance-critical code with care.
 ALWAYS_INLINE void FastPoisonShadow(uptr aligned_beg, uptr aligned_size,
                                     u8 value) {
-  DCHECK(CanPoisonMemory());
+  DCHECK(!value || CanPoisonMemory());
   uptr shadow_beg = MEM_TO_SHADOW(aligned_beg);
   uptr shadow_end = MEM_TO_SHADOW(
       aligned_beg + aligned_size - SHADOW_GRANULARITY) + 1;
diff --git a/compiler-rt/test/asan/TestCases/handle_noreturn_bug.cc b/compiler-rt/test/asan/TestCases/handle_noreturn_bug.cc
new file mode 100644
index 00000000000..8c3c66a423d
--- /dev/null
+++ b/compiler-rt/test/asan/TestCases/handle_noreturn_bug.cc
@@ -0,0 +1,13 @@
+// Regression test: __asan_handle_no_return should unpoison stack even with poison_heap=0.
+// RUN: %clangxx_asan -O0 %s -o %t && \
+// RUN: %env_asan_opts=poison_heap=1 %run %t && \
+// RUN: %env_asan_opts=poison_heap=0 %run %t
+
+#include <sanitizer/asan_interface.h>
+
+int main(int argc, char **argv) {
+  int x[2];
+  int * volatile p = &x[0];
+  __asan_handle_no_return();
+  int volatile z = p[2];
+}