AK: Print VERIFY() error messages in release builds

Until now, VERIFY() failures would just cause a __builtin_trap() in
release builds, which made them a bit too harsh. This commit adds an
out-of-line helper function that prints the error before trapping.

AK/Assertions.cpp

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <[email protected]>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/Assertions.h>
+#include <AK/Format.h>
+
+#if !defined(KERNEL) && defined(NDEBUG)
+extern "C" {
+
+void ak_verification_failed(char const* message)
+{
+ dbgln("VERIFICATION FAILED: {}", message);
+ __builtin_trap();
+}
+}
+
+#endif

AK/Assertions.h

@@ -13,9 +13,12 @@
 # ifndef NDEBUG
 # define VERIFY assert
 # else
-# define VERIFY(expr) \
- (__builtin_expect(!(expr), 0) \
- ? __builtin_trap() \
+# define __stringify_helper(x) # x
+# define __stringify(x) __stringify_helper(x)
+extern "C" __attribute__((noreturn)) void ak_verification_failed(char const*);
+# define VERIFY(expr) \
+ (__builtin_expect(!(expr), 0) \
+ ? ak_verification_failed(#expr "\n" __FILE__ ":" __stringify(__LINE__)) \
  : (void)0)
 # endif
 # define VERIFY_NOT_REACHED() VERIFY(false) /* NOLINT(cert-dcl03-c,misc-static-assert) No, this can't be static_assert, it's a runtime check */