pragma GCC diagnostic changes up with the binaries

Question

I was adding some GCC warning, and wanted to explicitly exclude some expressions and found a way by using #pragma diagnostic. However, I realized that depending where I put the pragma, the binaries can change.

For instance, consider the following snippet:

#include <stdio.h>

int f(int x, int y, int z);

int main()
{
    int x, y, z;
    scanf("%d%d%d", &x, &y, &z);
    f(x, y, z);
    return 0;
}

and the following two implementations of f(...):

1. https://godbolt.org/z/hxWcf6h9s

   • Implementation of f:

     int f(int x, int y, int z)
     {
         #pragma GCC diagnostic push
         #pragma GCC diagnostic ignored "-Wparentheses"
         if (x || y && z)
         #pragma GCC diagnostic pop
         {
             return 1;
         }
         return 0;
     }
     

   • Generated code:

     f:
             push    rbp
             mov     rbp, rsp
             mov     DWORD PTR [rbp-4], edi
             mov     DWORD PTR [rbp-8], esi
             mov     DWORD PTR [rbp-12], edx
             mov     eax, 1
             pop     rbp
             ret
     

2. https://godbolt.org/z/qdnhhKMjP

   • Implementation of f:

     int f(int x, int y, int z)
     {
         #pragma GCC diagnostic push
         #pragma GCC diagnostic ignored "-Wparentheses"
         if (x || y && z)
         {
         #pragma GCC diagnostic pop
             return 1;
         }
         return 0;
     }
     

   • Generated code:

     f:
             push    rbp
             mov     rbp, rsp
             mov     DWORD PTR [rbp-4], edi
             mov     DWORD PTR [rbp-8], esi
             mov     DWORD PTR [rbp-12], edx
             cmp     DWORD PTR [rbp-4], 0
             jne     .L2
             cmp     DWORD PTR [rbp-8], 0
             je      .L3
             cmp     DWORD PTR [rbp-12], 0
             je      .L3
     .L2:
             mov     eax, 1
             jmp     .L4
     .L3:
             mov     eax, 0
     .L4:
             pop     rbp
             ret
     

Compiled with gcc -std=gnu99 -Wparentheses -Werror -O0, result in different binaries. Why is that?