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Is there any substantial optimization when omitting the frame pointer? If I have understood correctly by reading this page, -fomit-frame-pointer is used when we want to avoid saving, setting up and restoring frame pointers. Is this done only for each function call and if so, is it really worth to avoid a few instructions for every function? Isn't it trivial for an optimization. What are the actual implications of using this option apart from the debugging limitations? I compiled the following C code with and without this option int main(void) { int i; i = myf(1, 2); } int myf(int a, int b) { return a + b; } , # gcc -S -fomit-frame-pointer code.c -o withoutfp.s # gcc -S code.c -o withfp.s . diff -u 'ing the two files revealed the following assembly code: --- withfp.s 2009-12-22 00:03:59.000000000 +0000 +++ withoutfp.s 2009-12-22 00:04:17.000000000 +0000 @@ -7,17 +7,14 @@ leal 4(%esp), %ecx andl $-16, %esp pushl -4(%ecx) - pushl %ebp - movl %esp, %ebp pushl %ecx - subl $36, %esp + subl $24, %esp movl $2, 4(%esp) movl $1, (%esp) call myf - movl %eax, -8(%ebp) - addl $36, %esp + movl %eax, 20(%esp) + addl $24, %esp popl %ecx - popl %ebp leal -4(%ecx), %esp ret .size main, .-main @@ -25,11 +22,8 @@ .globl myf .type myf, @function myf: - pushl %ebp - movl %esp, %ebp - movl 12(%ebp), %eax - addl 8(%ebp), %eax - popl %ebp + movl 8(%esp), %eax + addl 4(%esp), %eax ret .size myf, .-myf .ident "GCC: (GNU) 4.2.1 20070719

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