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Re: x86 double alignment (was egcs-1.1 release schedule)
- To: law at cygnus dot com
- Subject: Re: x86 double alignment (was egcs-1.1 release schedule)
- From: Michael Meissner <meissner at cygnus dot com>
- Date: Fri, 26 Jun 1998 10:16:36 -0400
- Cc: egcs at cygnus dot com
| > What I haven't looked into yet is whether subtracting 4 from %esp
| > before pushing args might upset some varargs/stdargs implementation
| > on the callee side (that the caller doesn't know about), i.e. if
| > that can even happen.
| I'm pretty sure it's safe. Even for varargs/stdarg. Basically think
| of it as having an extra int argument at the end of the arglist
| (remember we push back to front). An extra argument never hurt anyone :-)
|
| We do have to be careful and make sure we don't screw RETURN_POPS_ARGS
| support though. I'd forgotten about that. Though I do not think
| that adds any significant complexity to the problem.
Also you have to watch out for exception handling/debugging/dwarf2 frame
unwinds.