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Re: Infering that the condition of a for loop is initially true?
Marc Glisse <email@example.com> writes:
> assert is not what you want, since it completely disappears with
> -DNDEBUG. clang has __builtin_assume, with gcc you want a test and
> __builtin_unreachable. Replacing your assert with
To me, it would make sense to have assert expand to something like that,
when runtime checks are disabled with -NDEBUG.
After all, is a program fails an assertion, it can not be expected to
produce any meaningful results, even with run-time checks disabled using
-DNDEBUG. And it's somewhat counter-intutive, if -DNDEBUG produces a
binary in which the code downstream from assert statements are slightly
less well optimized.
I imagine the C standard might specify that assert "completely
disappears" if -DNDEBUG is defined. But maybe there's room for a
-fstrict-assert optimization flag, to let assert always guide
Niels Möller. PGP-encrypted email is preferred. Keyid 368C6677.
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