optimization bug: -O3 (-finline?) sometimes fails to keep a copy of a function.

[Doug Kilpatrick]

Test case consists of two files: driver.cxx and main.cxx

/* -------------  driver.cxx: ---------------- */

#include <stdio.h>

typedef void *(*fooFunc)(void *, void *, unsigned int);
typedef struct driver_struct
{
    fooFunc     foo;
    fooFunc     bar;
    fooFunc     baz;
} driver_struct;



static void * foo(void *vp, void *vp2, unsigned int ui)
{
    printf("Foo.\n");
    return NULL;
}

static const driver_struct driver = { foo, foo, foo };

void *api_hook(void *vp, void *vp2, unsigned int ui)
{
    return driver.foo(vp,vp2,ui);
}


/*------------------- main.cxx: ------------------- */
#include <stdlib.h>

extern void* api_hook(void *vp, void *vp2, unsigned int ui);

int main(int argc, char *argv[])
{
    return ((api_hook(NULL,NULL,0) == NULL));
}


Demonstration of the problem:

% g++ -O3 -c driver.cxx
% g++ -O3 -c main.cxx
% g++ -o a.out driver.o main.o
driver.o(.rodata+0x8): undefined reference to `foo(void *, void *,
unsigned int)'
driver.o(.rodata+0xc): undefined reference to `foo(void *, void *,
unsigned int)'
driver.o(.rodata+0x10): undefined reference to `foo(void *, void *,
unsigned int)'
collect2: ld returned 1 exit status
% g++ -O2 -c driver.cxx
% g++ -o a.out driver.o main.o
% ./a.out
Foo.
% 



Doug
-- doug@visix.com