Snippets for sbcl 2.6.8 from Fedora ppc64le

Sourced from https://kojipkgs.fedoraproject.org/packages/sbcl/2.6.8/1.fc46/data/logs/ppc64le/build.log.

• os-common.c:297:9: warning: ignoring return value of 'read' declared with attribute 'warn_unused_result' [-Wunused-result]
    297 |         read(fd, addr, len);
        |         ^~~~~~~~~~~~~~~~~~~
  

• ppc-linux-os.c:121:11: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
    121 |     d = *((double *) &control);
        |          ~^~~~~~~~~~~~~~~~~~~~
  

• monitor.c:336:17: warning: type of 'gc_and_save' does not match original declaration [-Wlto-type-mismatch]
    336 |     extern void gc_and_save(char*,bool,bool,bool,bool,int,int);
        |                 ^