Snippets for a2jmidid 9 from Alpine armv7

Sourced from https://build.alpinelinux.org/buildlogs/build-edge-armv7/testing/a2jmidid/a2jmidid-9-r3.log.

• ../sigsegv.c:68:12: warning: unused variable 'sz' [-Wunused-variable]
     68 |     size_t sz;
        |            ^~
  

• ../sigsegv.c:67:12: warning: unused variable 'strings' [-Wunused-variable]
     67 |     char **strings;
        |            ^~~~~~~
  

• ../sigsegv.c:66:11: warning: unused variable 'bt' [-Wunused-variable]
     66 |     void *bt[20];
        |           ^~
  

• ../sigsegv.c:58:17: warning: unused variable 'ucontext' [-Wunused-variable]
     58 |     ucontext_t *ucontext = (ucontext_t*)ptr;
        |                 ^~~~~~~~
  

• ../sigsegv.c:57:12: warning: unused variable 'i' [-Wunused-variable]
     57 |     size_t i;
        |            ^
  

• ../jack.c:64:18: warning: variable 'now' set but not used [-Wunused-but-set-variable]
     64 |   jack_nframes_t now;
        |                  ^~~
  

• ../jack.c:326:7: warning: variable 'err' set but not used [-Wunused-but-set-variable]
    326 |   int err;
        |       ^~~