Configuration for etc/*.c needs to set values for these variables:

	#ifndef GCCDIR		[etc: aix.c freebsd.c gcc-solaris.c hpux.c linux.c macosx.c 
				      ppc-linux.c sparc-linux.c]

	#ifndef GCCLIB		[etc: only in gcc-solaris.c]

	#ifndef LCCDIR		[etc: in /*.c]

	#ifndef LIBDIR		[etc: only in freebsd.c hpux.c irix.c linux.c]
				[On these systems, gcc is the native compiler]

	#ifndef LOCAL		[etc: only in aix.c macosx.c ppc-linux.c sparc-linux.c]

	#ifndef NATIVEDIR	[etc: solaris.c]

	#ifndef TEMPDIR		[etc: lcc.c]

Typical settings are:

	#define GCCDIR "/usr/lib/"
	#define GCCDIR "/usr/local/gnu/bin/"
	#define GCCDIR "/usr/local/lib/gcc-lib/hppa1.1-hp-hpux10.20/2.95.2/"
	#define GCCDIR "/usr/local/lib/gcc-lib/i386-unknown-freebsd3.0/2.8.1/"
	#define GCCDIR "/usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.95.2/"
	#define GCCDIR LOCAL "lib/gcc-lib/sparc-unknown-linux-gnu/2.95.2/"

	#define GCCLIB "/usr/local/gnu/lib/gcc-lib/sparc-sun-solaris2.5/2.7.2/"

	#define LCCDIR "/usr/local/lib/lcc/"
	#define LCCDIR "\\progra~1\\lcc\\4.1\\bin\\"
	#define LCCDIR LOCAL "lib/lcc/"

	#define LIBDIR "/usr/lib/"

	#define NATIVEDIR "/opt/SUNWspro/WS6U1/lib/"

Suitable files to look for are 
	GCCDIR "crtbegin.o"

	LCCDIR	-> INSTALLLIBDIR 
		== ${exec_prefix}/lib/lcc-${VERSIONNUMBER}
		== ${prefix}/lib/lcc-${VERSIONNUMBER}

	LOCAL	-> ${prefix}

The hard part may be GCCDIR:
	strings $B/gcc | grep /gcc-lib/ -> /usr/local/lib/gcc-lib/ 
	but the same thing 
	on FreeBSD turns up nothing for /usr/bin/cc, and for
	/usr/local/bin/gcc, finds
	/usr/local/lib/gcc-lib/i386-unknown-freebsd3.0/2.8.1/specs
	Similarly, on rhapsody, nothing is found.

This suggests that we try $(prefix)/lib/gcc-lib, then /usr/lib, and search for
crt1.o, but allow the user to provide a configure-time setting of
GCCDIR to override this choice, and ditto for LIBDIR.

