This happened to me when I wanted to look at assembler output source using gcc -S and for better readability choose -masm=intel option. -S only works fine. I tried to cut my source and include short example which can be quickly verified. I also checked this problem happen on mingw32 gcc ver 3.4.5

Try to compile this: gcc -S x.c -masm=intel

x.c:
=================================
#include <stdlib.h>
#include <stdio.h>

typedef struct {
unsigned long offset; // 32-bit offset
unsigned short selector; // 16-bit selector
} __attribute__((packed)) PM_FAR_POINTER;

int exec_ring0_code(unsigned long code_address, unsigned long ecx, unsigned long *eax, unsigned long *edx)
{
PM_FAR_POINTER callgate_ptr;
asm __volatile__ (
"lcall *%5\n"
: "=a"(*eax), "=d"(*edx)
: "a"(*eax), "c"(ecx), "d"(*edx), "m" (callgate_ptr)
: "memory"
);
return(0);
}
=================================

result is:

x.c: In function 'exec_ring0_code':
x.c:19: internal compiler error: in print_operand, at config/i386/i386.c:7961
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.

Assembler output x.S stops at line
"lcall *"

when I compile it with gcc -S x.c only it compile all without error
and mentioned line looks this:
"lcall *-6(%ebp)"