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I can't see any difference of code by gcc for restrict pointers. file1 void test (int *a, int *b, int *c) { while (*a) { *c++ = *a++ + *b++; } } file2 void test (int *restrict a, int *restrict b, int *restrict c) { while (*a) { *c++ = *a++ + *b++; } } compile with gcc -S -std=c99 -masm=intel file1.c gcc -S -std=c99 -masm=intel file2.c file1.s and file2.s both are same, except the .file line, which tells the filename: .file "file1.c" .text .globl test .type test, @function test: .LFB0: .cfi_startproc pushq %rbp .cfi_def_cfa_offset 16 .cfi_offset 6, -16 movq %rsp, %rbp .cfi_def_cfa_register 6 movq %rdi, -8(%rbp) movq %rsi, -16(%rbp) movq %rdx, -24(%rbp) jmp .L2 .L3: movq -8(%rbp), %rax movl (%rax), %edx movq -16(%rbp), %rax movl (%rax), %eax addl %eax, %edx movq -24(%rbp), %rax movl %edx, (%rax) addq $4, -24(%rbp) addq $4, -8(%rbp) addq $4, -16(%rbp) .L2: movq -8(%rbp), %rax movl (%rax), %eax testl %eax, %eax jne .L3 popq %rbp .cfi_def_cfa 7, 8 ret .cfi_endproc .LFE0: .size test, .-test .ident "GCC: (GNU) 4.6.3 20120306 (Red Hat 4.6.3-2)" .section .note.GNU-stack,"",@progbits Both of these code read from the memory and then assign the memory location pointed to by a to b . Where i expected the restrict version will not re-read the addresses of a and b , and the addresses of a and b will be incremented in-register and at the end written to memory. Is there anything wrong i am doing? Or is the selection of the example okay?<

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