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> > | Hi, > | > | This is a very old bug date back to 1.38.1. The reason no one really > | cares is gcc won't generate that kind of code, i.e., jump out of range. > | When some Linux people were working on X11R5, they used an Intel x86 > | branch/loop instruction, jcxz, which has only byte displacements in > | the hand coded asm code. The AT&T as worked fine with expansion. But > | gas 1.38.1 generated some bogus codes. I fixed the bug for them. I > | think it is correct. The test case is very easy to produce. Please let > | me know if you need one. > > While it should be certainly fixed in the assembler, the X11 code > should also replace the jcxz instruction with a compare against 0 and > jmp sequence, since that is faster on anything but an original 386. > See the optimization guides in the 486/pentium manuals. > > After I told them that, they have then changed the code. -- H.J. Lu NYNEX Science and Technology, Inc. hjl@nynexst.com