Try to find a compiler option that enables usage of char-type to index a value-field. This one needs unsigned-chars and it must suppress warnings about usage of chars for subscripting. for gcc -funsigned-char -Wno-char-subscripts
Currently this macro knows about GCC. hopefully will evolve to use: Solaris C compiler, Digital Unix C compiler, C for AIX Compiler, HP-UX C compiler, and IRIX C compiler.
Download the latest version of ax_prog_cc_char_subscripts.m4 or browse the macro’s revision history.
Copyright © 2008 Guido U. Draheim email@example.com
Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved. This file is offered as-is, without any warranty.