From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Kettenis To: eliz@is.elta.co.il Cc: gdb@sources.redhat.com Subject: Re: i386 register numbering Date: Sat, 28 Jul 2001 11:02:00 -0000 Message-id: <200107281802.f6SI27819117@delius.kettenis.local> References: <200107281012.GAA02314@delorie.com> <200107281214.IAA07439@delorie.com> X-SW-Source: 2001-07/msg00398.html Date: Sat, 28 Jul 2001 08:14:26 -0400 From: Eli Zaretskii DJGPP supports 3 debug info formats: COFF, stabs, and (lately) DWARF2; the default is COFF. (Btw, I don't see any COFF_REG_TO_REGNUM.) I'm guessing that no one (including myself ;-) bothered to review the register naming scheme when support for stabs and DWARF2 was added... With the patch that I just checked in, COFF and stabs should do the right thing for DJGPP. DWARF2 will probably still give you the wrong register. You might want to consider changing GCC such that it uses the standard Dwarf renumbering for DWARF2. I don't think it really matters since there aren't any native tools that you need to be compatible with. On the other hand, using DWARF2 with a numbering scheme that nobody else uses, might trigger some bugs. If you don't change GCC you should probably override DWARF2_REG_TO_REGNO in config/i386/tm-go32.h. But there's something in your explanation that I don't get: if GCC always uses the same scheme, no matter what the debug info, and since all i386 targets use the same i386.h header which defines this scheme, how come DJGPP can use something different than the other targets? What am I missing? Several GCC targets redefine DBX_REGISTER_NUMBER, see for example linux.h in that same directory. Mark