-03 & inlining & computed goto bug

[Kent Boortz]

problem:	the resulting code is wrong if using -O3 and computed goto
version:	EGCS 1.0.2, GCC 2.8.1, GCC 2.7.X
uname -a:	SunOS gollum 5.5.1 Generic_103640-18 sun4u sparc SUNW,Ultra-1
command:	gcc -O3 test.c
error msg:	-

The program below is not running properly if inlining is used together
with -O3 optimisation. I believe it is a target independent bug, I saw
it first on gcc 2.7.X for m68k. The code below is only tested to be
incorrect on Sparc.

The problem goes away if using "gcc -O3 -fno-inline test.c".

/kgb

---------------------------------------------------------------------------
int expect_do1 = 1, expect_do2 = 2;
 
static int doit(int x){
  __label__ lbl1;
  __label__ lbl2;
  static int jtab_init = 0;
  static void *jtab[2];
 
  if(!jtab_init) {
    jtab[0] = &&lbl1;
    jtab[1] = &&lbl2;
    jtab_init = 1;
  }
  goto *jtab[x];
lbl1:
  return 1;
lbl2:
  return 2;
}
 
static void do1(void) {
  if (doit(0) != expect_do1)
    exit(1);
}
 
static void do2(void){
  if (doit(1) != expect_do2)
    exit(2);
}
 
int main(void){
  do1();
  do2();
  exit(0);
}
---------------------------------------------------------------------------