antlr3 C runtime generates incorrect ABI flags for non x86 with gcc

[sternenseemann]

If --enable-64bit and --enable-abiflags are passed to the configure script, it'll decide on passing -m64. This option however implies x86 and will fail e. g. on aarch64. A similar thing will probably also happen on 32 bit non-x86 architectures when --enable-64bit is not passed.

See the gcc manual for -m32 and -m64.

This is the offending code:

antlr3/runtime/C/configure.ac

Lines 93 to 108 in 5c2a916

	gcc*)
	CPPCMNTFLAGS=
	if test x"$enable_64bit" = xyes; then
	GCCABIFLAGS="-m64"
	else
	GCCABIFLAGS="-m32"
	fi
	if test x"$enable_abiflags" = xyes; then
	CCFLAGS64=$GCCABIFLAGS
	fi
	OPTIMFLAGS="-O2"
	if test x"$enable_debuginfo" = xyes; then
	DEBUGFLAGS="-g"
	fi
	WARNFLAGS=-Wall
	;;

[aptok]

Run into this while building OpenModelica on aarch64 and manually changed GCCABIFLAGS="-m64" to GCCABIFLAGS="-march=armv8-a".