This is the mail archive of the gcc@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Potential bug in jump optimization?


<aspiesrule@mcleodusa.net> writes:

> If a move to CR0 which sets the PE bit is executed and GCC's jump optimizer 
> optimizes away the far jump/call that must occur immediately afterwards, the 
> resulting code can and will fail.

Bare-metal code like that belongs in handwritten assembly language
files, not in C inline asm.

This is a special case of the general rule that inline asm statements
cannot change control flow.

zw


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]