i386, asm() and "o" constraint

Alexander Melkov melkov@yandex-team.ru
Wed Sep 24 19:54:00 GMT 2003

Before writing to bugs, I thought it would be appropriate to ask it here:
Does anyone know if that is implemented in latest GCC releases? gcc-3.1.1, just like 2.95.x, says
"warning: asm operand 5 probably doesn't match constraints".

What I actually need is to have an instruction like "adcl %3,4+%1" compiled without useless (both
compiler and assembler) warnings, where %1 is a memory reference, say, "=o" (Sum), where Sum is a
64-bit integer.

Unlike "m", "o" might simply write "0(%ebp)" instead of just "(%ebp)".

Best Regards, Alexander Melkov

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