[libcxx-commits] [libcxx] [libc++][hardening] Add a greppable prefix to assertion messages. (PR #150560)

[Louis Dionne via libcxx-commits]

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@@ -20,8 +20,8 @@
 #define _LIBCPP_ASSERT(expression, message)                                                                            \
   (__builtin_expect(static_cast<bool>(expression), 1)                                                                  \
        ? (void)0                                                                                                       \
-       : _LIBCPP_ASSERTION_HANDLER(__FILE__ ":" _LIBCPP_TOSTRING(__LINE__) ": assertion " _LIBCPP_TOSTRING(            \
-             expression) " failed: " message "\n"))
+       : _LIBCPP_ASSERTION_HANDLER(__FILE__ ":" _LIBCPP_TOSTRING(                                                      \
+             __LINE__) ": libc++ Hardening assertion " _LIBCPP_TOSTRING(expression) " failed: " message "\n"))
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ldionne wrote:

> Do we intend for `_LIBCPP_ASSERT` to only ever be used for hardening?

I think it depends how you think about it. Many existing assertions are technically not really "hardening" in the sense of "security hardening". But since we've decided to classify all of the assertions and simply discriminate them based on the mode selected by the user, we consider all of them to be part of "Hardening" (as in, the libc++ extension).

So because of that, yes I think that `_LIBCPP_ASSERT` will always be used for "libc++ Hardening" related checks (since by definition any check we might add would fall into it), but not all of them are true "security hardening" in the general sense of it. True "security hardening" checks would be closer to the ones included in the fast (and maybe extensive) modes, probably without any check that is purely pedantic in nature.

https://github.com/llvm/llvm-project/pull/150560