> -----Original Message----- > From: John Regehr [mailto:[EMAIL PROTECTED] > Sent: Monday, October 01, 2007 10:59 PM > To: Eric Weddington > Cc: 'Paulo Marques'; 'David Brown'; 'AVR-GCC' > Subject: RE: [avr-gcc-list] Problem with delay loop > > > However, David brings up a good point. A local variable is > put on the stack, > > generally not the place for hardware to modify the > variable. And generally, > > other parts of the program (such as ISRs) don't have access > to the specific > > location of the variable on the stack. Both hardware and > ISRs work with > > global variables. So *could* a compiler reason that local > variables could > > never be volatile? Or are there truly situations where > hardware or ISRs > > could modify local variables on the stack? > > The common use of volatile automatic variables is in conjunction with > setjmp/longjmp. This idiom would break if volatile locals went into > registers.
Ah, ok then. In practice, I have never needed to use setjmp/longjmp, so I have a tendency to forget about these routines. Thanks, Eric _______________________________________________ AVR-GCC-list mailing list AVR-GCC-list@nongnu.org http://lists.nongnu.org/mailman/listinfo/avr-gcc-list
