[rtsan] Introduce halt_on_error flag (llvm#109832)

Author: cjappl

compiler-rt/lib/rtsan/rtsan.cpp

@@ -44,10 +44,11 @@ static InitializationState GetInitializationState() {
       atomic_load(&rtsan_initialized, memory_order_acquire));
 }
 
-static auto PrintDiagnosticsAndDieAction(DiagnosticsInfo info) {
+static auto OnViolationAction(DiagnosticsInfo info) {
   return [info]() {
     __rtsan::PrintDiagnostics(info);
-    Die();
+    if (flags().halt_on_error)
+      Die();
   };
 }
 
@@ -105,20 +106,18 @@ __rtsan_notify_intercepted_call(const char *func_name) {
 
   __rtsan_ensure_initialized();
   GET_CALLER_PC_BP;
-  ExpectNotRealtime(
-      GetContextForThisThread(),
-      PrintDiagnosticsAndDieAction(
-          {DiagnosticsInfoType::InterceptedCall, func_name, pc, bp}));
+  ExpectNotRealtime(GetContextForThisThread(),
+                    OnViolationAction({DiagnosticsInfoType::InterceptedCall,
+                                       func_name, pc, bp}));
 }
 
 SANITIZER_INTERFACE_ATTRIBUTE void
 __rtsan_notify_blocking_call(const char *func_name) {
   __rtsan_ensure_initialized();
   GET_CALLER_PC_BP;
-  ExpectNotRealtime(
-      GetContextForThisThread(),
-      PrintDiagnosticsAndDieAction(
-          {DiagnosticsInfoType::BlockingCall, func_name, pc, bp}));
+  ExpectNotRealtime(GetContextForThisThread(),
+                    OnViolationAction({DiagnosticsInfoType::BlockingCall,
+                                       func_name, pc, bp}));
 }
 
 } // extern "C"

compiler-rt/lib/rtsan/rtsan_flags.inc

@@ -16,5 +16,4 @@
 // RTSAN_FLAG(Type, Name, DefaultValue, Description)
 // See COMMON_FLAG in sanitizer_flags.inc for more details.
 
-// Example flag, until we get a real one
-// RTSAN_FLAG(bool, halt_on_error, true, "If true, halt the program on error")
+RTSAN_FLAG(bool, halt_on_error, true, "Exit after first reported error.")

compiler-rt/test/rtsan/halt_on_error.cpp

@@ -0,0 +1,26 @@
+// RUN: %clangxx -fsanitize=realtime %s -o %t
+// RUN: %env_rtsan_opts="halt_on_error=true" not %run %t 2>&1 | FileCheck %s
+// RUN: %env_rtsan_opts="halt_on_error=false" %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK-NO-HALT,CHECK
+// UNSUPPORTED: ios
+
+// Intent: Ensure that halt_on_error does not exit on the first violation.
+
+#include <stdlib.h>
+
+void *MallocViolation() { return malloc(10); }
+
+void FreeViolation(void *Ptr) { free(Ptr); }
+
+void process() [[clang::nonblocking]] {
+  void *Ptr = MallocViolation();
+  FreeViolation(Ptr);
+}
+
+int main() {
+  process();
+  return 0;
+  // CHECK: ==ERROR: RealtimeSanitizer
+  // CHECK-NEXT: {{.*`malloc`.*}}
+  // CHECK-NO-HALT: ==ERROR: RealtimeSanitizer
+  // CHECK-NO-HALT-NEXT: {{.*`free`.*}}
+}