Snippets for postgresql 18.6 from Nix aarch64-darwin

Sourced from https://hydra.nixos.org/log/qr502ygxg7g9awjy9aphvdilxlc9w0py-postgresql-18.6.drv.

• exec.c:249:11: warning: mixing declarations and code is incompatible with standards before C99 [-Wdeclaration-after-statement]
    249 |         char       *abspath = pg_realpath(path);
        |                     ^
  

• pg_config.c:25:17: warning: unused variable 'rsinfo' [-Wunused-variable]
     25 |         ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
        |                        ^~~~~~
  

• pg_config.c:26:14: warning: unused variable 'configdata' [-Wunused-variable]
     26 |         ConfigData *configdata;
        |                     ^~~~~~~~~~
  

• pg_config.c:27:10: warning: unused variable 'configdata_len' [-Wunused-variable]
     27 |         size_t          configdata_len;
        |                         ^~~~~~~~~~~~~~
  

• pg_config.c:28:8: warning: unused variable 'i' [-Wunused-variable]
     28 |         int                     i = 0;
        |                                 ^