A Power AIX build with fortran enabled fails in stage2, because longjmp is not declared noreturn in system header files. That is probably only true on systems where gcc is the system compiler, since this is a GCC extension.
.../../gcc-git/gcc/fortran/parse.c: In function 'void unexpected_eof()': .../../gcc-git/gcc/fortran/parse.c:2740:1: error: 'noreturn' function does return [-Werror] } ^ If I drop ATTRIBUTE_NORETURN on the unexpected_eof declaration, then I get 18 errors that look like this one. This is stage2 of a linux build. .../../gcc-svn/gcc/fortran/parse.c: In function ‘gfc_statement parse_spec(gfc_statement)’: .../../gcc-svn/gcc/fortran/parse.c:3745:22: error: this statement may fall through [-Werror=implicit-fallthrough=] unexpected_eof (); ~~~~~~~~~~~~~~~^~ .../../gcc-svn/gcc/fortran/parse.c:3747:5: note: here case ST_IMPLICIT_NONE: ^~~~ If I add a call to gcc_unreachable after the longjmp call, then it builds on both linux and AIX. Anyone have a better idea on how to fix this? If I don't get any responses in a few days, I will check it in under the obvious rule, since it fixes a build failure. Jim
2017-10-29 Jim Wilson <wil...@tuliptree.org> gcc/fortran/ * parse.c (unexpected_eof): Call gcc_unreachable before return. Index: gcc/fortran/parse.c =================================================================== --- gcc/fortran/parse.c (revision 254210) +++ gcc/fortran/parse.c (working copy) @@ -2737,6 +2737,9 @@ unexpected_eof (void) gfc_done_2 (); longjmp (eof_buf, 1); + + /* Avoids build error on systems where longjmp is not declared noreturn. */ + gcc_unreachable (); }
