Optimizer bug, gcc 4.1.2

["Duijneveld, PW - SPLXM" <paula dot duijneveld at klm dot com>]

Hi,

Program runs fine with no optimization, fails with O3

The essentials (I think) of the offending code:

Static inline int f(char ** ppc);

Int f(char ** ppc) {
  ..
  *ppc = ...
  Return ...
  }

In main:

Unsigned char * pc = NULL;

If (f(&pc) == -1) {
  ..
  } 
Else {
  If (pc) {
    ..
    .. 

Using O3, the test if (pc) always fails because the generated code tests
the value of pc before pc is updated as a result of the function call.

Changing the definition of pc to char * makes the code work properly.

I thought that unsigned char and char were equivalent?

Regards,
Paula Duijneveld 
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