Stack alignment in gcc-ss-20000828

[David Ronis <ronis at ronispc dot chem dot mcgill dot ca>]

This bug was pointed out by Steven Johnson some time ago.  It's still
seems to be present in gcc-ss-20000828, compiled on an i686-linux-gnu.
I'm running linux-2.2.16 and glibc-2.1.3 and Binutils (2.9.1.0.7) GNU
ld version 2.10.90 (with BFD 2.10.90).

The compiler was built with:

configure flags:  --host=i686-pc-linux --prefix=/usr --with-gnu-as
                  --enable-shared --with-gnu-ld

CFLAGS=CXXFLAGS=BOOT_CFLAGS=-O3 -march=i686 -funroll-loops -ffast-math
                                -fomit-frame-pointer -fforce-mem 
                                -fforce-addr -malign-jumps=3
                                -malign-functions=3 -malign-loops=3

(for testsuite results, see
     http://gcc.gnu.org/ml/gcc-testresults/2000-08/msg00246.html)

The test code is:

----------------------------stack2.c-----------------------------------
int one(int count)
{
     double foobar;
     if ((((long) &foobar) & 0x7L)) {
          printf("one %d\n", count);
          abort();
     }
     return 1;
}

void blah(int foo)
{
     double foobar;
     if ((((long) &foobar) & 0x7L)) {
          printf("blah\n");
          abort();
     }
}

int main(void)
{
     one(1);
     blah(one(2));
     return 0;
}

---------------------------------------------------------------------------

Which when compiled as,

/usr/bin/gcc -malign-functions=3 -malign-jumps=3
 -mpreferred-stack-boundary=3 -save-temps stack2.c

and run gives:

a.out
one 1
Abort

Here's the .s file (there are no #includes, so the .i file is
essentially the same as the .c):

        .file   "stack2.c"
        .version        "01.01"
gcc2_compiled.:
                .section        .rodata
.LC0:
        .string "one %d\n"
.text
        .align 8
.globl one
        .type    one,@function
one:
        pushl   %ebp
        movl    %esp, %ebp
        subl    $8, %esp
        leal    -8(%ebp), %eax
        andl    $7, %eax
        testl   %eax, %eax
        je      .L3
        pushl   8(%ebp)
        pushl   $.LC0
        call    printf
        addl    $8, %esp
        call    abort
        .p2align 3
.L3:
        movl    $1, %eax
        movl    %ebp, %esp
        popl    %ebp
        ret
.Lfe1:
        .size    one,.Lfe1-one
                .section        .rodata
.LC1:
        .string "blah\n"
.text
        .align 8
.globl blah
        .type    blah,@function
blah:
        pushl   %ebp
        movl    %esp, %ebp
        subl    $8, %esp
        leal    -8(%ebp), %eax
        andl    $7, %eax
        testl   %eax, %eax
        je      .L5
        subl    $4, %esp
        pushl   $.LC1
        call    printf
        addl    $8, %esp
        call    abort
        .p2align 3
.L5:
        movl    %ebp, %esp
        popl    %ebp
        ret
.Lfe2:
        .size    blah,.Lfe2-blah
        .align 8
.globl main
        .type    main,@function
main:
        pushl   %ebp
        movl    %esp, %ebp
        subl    $8, %esp
        subl    $4, %esp
        pushl   $1
        call    one
        addl    $8, %esp
        subl    $4, %esp
        pushl   $2
        call    one
        addl    $4, %esp
        movl    %eax, -4(%ebp)
        pushl   -4(%ebp)
        call    blah
        addl    $8, %esp
        movl    $0, %eax
        movl    %ebp, %esp
        popl    %ebp
        ret
.Lfe3:
        .size    main,.Lfe3-main
        .ident  "GCC: (GNU) 2.96 20000828 (experimental)"