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Re: [PATCH] doc - document how gcc relies on the length of an asm
>>>>> "Falk" == Falk Hueffner <firstname.lastname@example.org> writes:
Falk> Richard Earnshaw <email@example.com> writes:
>> This is a documentation update in response to PR 11442 where the
>> user had put a .skip directive in an ASM statement and this broke
>> GCC's asm size estimation rules. It tries to make it clear that
>> this is a user error that will only be detected by the assembler.
Falk> It should be mentioned that this might not only lead to
Falk> assembler errors, but also to silently generated bad code (PR
That's an assembler bug, right?
Falk> By the way, would it be possible to assert gcc's guess for the
Falk> size of an asm by putting a label before and after it and
Falk> emitting an ".assert" directive or something? That might avoid
Falk> such errors.
Not a bad idea so long as it's a range check (i.e., assert that the
estimate is a correct upper bound). Sometimes it's quite hard to make
the estimate exact, so the backend ends up producing a reasonably
tight upper bound.