ncopa-desktop:~/src/fortify-headers (master)$ make -C tests
make: Entering directory '/var/ncopa/src/fortify-headers/tests'
make: ../x86_64-linux-musl-native/bin/gcc: No such file or directory
make: *** [Makefile:178: test_FD_CLR_SETSIZE] Error 127
make: Leaving directory '/var/ncopa/src/fortify-headers/tests'

ncopa-desktop:~/src/fortify-headers (master)$ make -C tests CC=gcc
make: Entering directory '/var/ncopa/src/fortify-headers/tests'                                                                                                                     
<command-line>: warning: "_FORTIFY_SOURCE" redefined                                                                                                                                
<built-in>: note: this is the location of the previous definition                                                                                                                   
In file included from ../include/unistd.h:26,                                                                                                                                       
                 from common.h:19,                                                                                                                                                  
                 from test_FD_CLR_SETSIZE.c:1:                                                                                                                                      
../include/unistd.h:48:13: error: 'confstr' undeclared here (not in a function)           
   48 | _FORTIFY_FN(confstr) size_t confstr(int __n, char * _FORTIFY_POS0 __s, size_t __l)                                                                                          
      |             ^~~~~~~
../include/fortify-headers.h:68:40: note: in definition of macro '_FORTIFY_ORIG'
   68 | #define _FORTIFY_ORIG(p,fn) __typeof__(fn) __orig_##fn __asm__(_FORTIFY_STR(p) #fn)
      |                                        ^~
../include/fortify-headers.h:70:25: note: in expansion of macro '_FORTIFY_FNB'
   70 | #define _FORTIFY_FN(fn) _FORTIFY_FNB(fn); _FORTIFY_INLINE
      |                         ^~~~~~~~~~~~
../include/unistd.h:48:1: note: in expansion of macro '_FORTIFY_FN'
   48 | _FORTIFY_FN(confstr) size_t confstr(int __n, char * _FORTIFY_POS0 __s, size_t __l) 
      | ^~~~~~~~~~~
../include/unistd.h:48:1: warning: 'access' attribute only applies to function types [-Wattributes]
../include/unistd.h:48:22: error: unknown type name 'size_t'
   48 | _FORTIFY_FN(confstr) size_t confstr(int __n, char * _FORTIFY_POS0 __s, size_t __l) 
      |                      ^~~~~~
../include/unistd.h:27:1: note: 'size_t' is defined in header '<stddef.h>'; this is probably fixable by adding '#include <stddef.h>'
   26 | #include "fortify-headers.h"
  +++ |+#include <stddef.h>
   27 | 
...
...
...
test_FD_CLR_SETSIZE.c:10:3: note: in expansion of macro 'CHK_FAIL_END'
   10 |   CHK_FAIL_END
      |   ^~~~~~~~~~~~
common.h:54:17: note: 'stderr' is defined in header '<stdio.h>'; this is probably fixable by adding '#include <stdio.h>'
   54 |   do { fprintf (stderr, "Failure in %s:%d\n", __FILE__, __LINE__); ret = 1; } while (0)
      |                 ^~~~~~
common.h:61:7: note: in expansion of macro 'FAIL'
   61 |       FAIL ();                                  \
      |       ^~~~
test_FD_CLR_SETSIZE.c:10:3: note: in expansion of macro 'CHK_FAIL_END'
   10 |   CHK_FAIL_END
      |   ^~~~~~~~~~~~
test_FD_CLR_SETSIZE.c:12:3: error: implicit declaration of function 'puts' [-Wimplicit-function-declaration]
   12 |   puts((const char*)&rfds);
      |   ^~~~
test_FD_CLR_SETSIZE.c:12:3: note: include '<stdio.h>' or provide a declaration of 'puts'
make: *** [Makefile:178: test_FD_CLR_SETSIZE] Error 1
make: Leaving directory '/var/ncopa/src/fortify-headers/tests'

<command-line>: warning: "_FORTIFY_SOURCE" redefined                                                                                                                                
<built-in>: note: this is the location of the previous definition