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 firstname.lastname@example.org
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