V2.x. Back-port PR #2334 to the v2.x branch

include/internal/catch_fatal_condition.cpp

@@ -85,7 +85,7 @@ namespace Catch {
         { static_cast<DWORD>(EXCEPTION_INT_DIVIDE_BY_ZERO), "Divide by zero error" },
     };
 
-    static LONG CALLBACK handleVectoredException(PEXCEPTION_POINTERS ExceptionInfo) {
+    static LONG CALLBACK topLevelExceptionFilter(PEXCEPTION_POINTERS ExceptionInfo) {
         for (auto const& def : signalDefs) {
             if (ExceptionInfo->ExceptionRecord->ExceptionCode == def.id) {
                 reportFatal(def.name);
@@ -99,7 +99,7 @@ namespace Catch {
     // Since we do not support multiple instantiations, we put these
     // into global variables and rely on cleaning them up in outlined
     // constructors/destructors
-    static PVOID exceptionHandlerHandle = nullptr;
+    static LPTOP_LEVEL_EXCEPTION_FILTER previousTopLevelExceptionFilter = nullptr;
 
 
     // For MSVC, we reserve part of the stack memory for handling
@@ -121,18 +121,15 @@ namespace Catch {
 
 
     void FatalConditionHandler::engage_platform() {
-        // Register as first handler in current chain
-        exceptionHandlerHandle = AddVectoredExceptionHandler(1, handleVectoredException);
-        if (!exceptionHandlerHandle) {
-            CATCH_RUNTIME_ERROR("Could not register vectored exception handler");
-        }
+        // Register as a the top level exception filter.
+        previousTopLevelExceptionFilter = SetUnhandledExceptionFilter(topLevelExceptionFilter);
     }
 
-    void FatalConditionHandler::disengage_platform() {
-        if (!RemoveVectoredExceptionHandler(exceptionHandlerHandle)) {
-            CATCH_RUNTIME_ERROR("Could not unregister vectored exception handler");
+    void FatalConditionHandler::disengage_platform() noexcept {
+        if (SetUnhandledExceptionFilter(previousTopLevelExceptionFilter) != topLevelExceptionFilter) {
+            CATCH_RUNTIME_ERROR("Could not restore previous top level exception filter");
         }
-        exceptionHandlerHandle = nullptr;
+        previousTopLevelExceptionFilter = nullptr;
     }
 
 } // end namespace Catch

include/internal/catch_fatal_condition.h

@@ -31,7 +31,7 @@ namespace Catch {
         // Should be if-defed to work on current platform, can assume
         // engage-disengage 1:1 pairing.
         void engage_platform();
-        void disengage_platform();
+        void disengage_platform() noexcept;
     public:
         // Should also have platform-specific implementations as needed
         FatalConditionHandler();

projects/SelfTest/UsageTests/Misc.tests.cpp

@@ -7,6 +7,7 @@
  */
 
 #include "catch.hpp"
+#include "internal/catch_windows_h_proxy.h"
 
 #ifdef __clang__
 #   pragma clang diagnostic ignored "-Wc++98-compat"
@@ -490,4 +491,48 @@ TEMPLATE_TEST_CASE_SIG("#1954 - 7 arg template test case sig compiles", "[regres
     SUCCEED();
 }
 
+// MinGW doesn't support __try, and Clang has only very partial support
+#if defined(_MSC_VER)
+void throw_and_catch()
+{
+    __try {
+        RaiseException(0xC0000005, 0, 0, NULL);
+    }
+    __except (1)
+    {
+
+    }
+}
+
+
+TEST_CASE("Validate SEH behavior - handled", "[approvals][FatalConditionHandler][CATCH_PLATFORM_WINDOWS]")
+{
+    // Validate that Catch2 framework correctly handles tests raising and handling SEH exceptions.
+    throw_and_catch();
+}
+
+void throw_no_catch()
+{
+    RaiseException(0xC0000005, 0, 0, NULL);
+}
+
+TEST_CASE("Validate SEH behavior - unhandled", "[.approvals][FatalConditionHandler][CATCH_PLATFORM_WINDOWS]")
+{
+    // Validate that Catch2 framework correctly handles tests raising and not handling SEH exceptions.
+    throw_no_catch();
+}
+
+static LONG CALLBACK dummyExceptionFilter(PEXCEPTION_POINTERS /*ExceptionInfo*/) {
+    return EXCEPTION_CONTINUE_SEARCH;
+}
+
+TEST_CASE("Validate SEH behavior - no crash for stack unwinding", "[approvals][!throws][!shouldfail][FatalConditionHandler][CATCH_PLATFORM_WINDOWS]")
+{
+    // Trigger stack unwinding with SEH top-level filter changed and validate the test fails expectedly with no application crash
+    SetUnhandledExceptionFilter(dummyExceptionFilter);
+    throw 1;
+}
+
+#endif // _MSC_VER
+
 }} // namespace MiscTests