Handle page protection errors by default as D errors on Linux

dlang · Jul 11, 2018 · 288c872 · 288c872
1 parent b5d124a
commit 288c872
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Showing 4 changed files with 31 additions and 1 deletion.
diff --git a/changelog/trap_memory_error.dd b/changelog/trap_memory_error.dd
@@ -0,0 +1,18 @@
+Page protection errors are now handled using D errors (exceptions) on Linux
+
+Consider this simple faulty program:
+
+---
+void main() {
+    int* ptr = null;
+    (*ptr)++;
+}
+---
+
+$(CONSOLE dmd -g -run test.d
+etc.linux.memoryerror.NullPointerError@src/etc/linux/memoryerror.d(325)
+$(NDASH)$(NDASH)$(NDASH)$(NDASH)$(NDASH)$(NDASH)$(NDASH)$(NDASH)$(NDASH)$(NDASH)
+??:? void etc.linux.memoryerror.sigsegvUserspaceProcess(void*) [0x8353df09]
+??:? void etc.linux.memoryerror.sigsegvDataHandler() [0x8353de4a]
+test.d:2 _Dmain [0x8353c2b5]
+)
diff --git a/src/rt/dmain2.d b/src/rt/dmain2.d
@@ -454,6 +454,13 @@ extern (C) int _d_run_main(int argc, char **argv, MainFunc mainFunc)
 
     bool trapExceptions = rt_trapExceptions;
 
+    // Handle page protection errors using D errors (exceptions) when supported
+    version (linux)
+    {
+        import etc.linux.memoryerror : registerMemoryErrorHandler;
+        registerMemoryErrorHandler();
+    }
+
     version (Windows)
     {
         if (IsDebuggerPresent())

diff --git a/test/exceptions/Makefile b/test/exceptions/Makefile
@@ -3,7 +3,7 @@ include ../common.mak
 TESTS:=stderr_msg unittest_assert invalid_memory_operation unknown_gc static_dtor future_message
 
 ifeq ($(OS)-$(BUILD),linux-debug)
-	TESTS:=$(TESTS) line_trace rt_trap_exceptions
+	TESTS:=$(TESTS) line_trace rt_trap_exceptions rt_trap_memory_error
 	LINE_TRACE_DFLAGS:=-L--export-dynamic
 endif
 ifeq ($(OS)-$(BUILD),freebsd-debug)
@@ -48,6 +48,7 @@ $(ROOT)/future_message.done: STDERR_EXP="exception I have a custom message. exce
 $(ROOT)/static_dtor.done: NEGATE=!
 $(ROOT)/rt_trap_exceptions.done: STDERR_EXP="uncaught exception\nobject.Exception@rt_trap_exceptions.d(11): exception"
 $(ROOT)/rt_trap_exceptions.done: NEGATE=!
+$(ROOT)/rt_trap_memory_error.done: STDERR_EXP="etc.linux.memoryerror.NullPointerError@src/etc/linux/memoryerror.d"
 $(ROOT)/%.done: $(ROOT)/%
 	@echo Testing $*
 	$(NEGATE) $(QUIET)$(TIMELIMIT)$(ROOT)/$* $(RUN_ARGS) 2>&1 1>/dev/null | grep -qF $(STDERR_EXP)

diff --git a/test/exceptions/src/rt_trap_memory_error.d b/test/exceptions/src/rt_trap_memory_error.d
@@ -0,0 +1,4 @@
+void main() {
+    int* ptr = null;
+    (*ptr)++;
+}