I figured out a simple way to cross-build while completely separating build-time objects from target objects. Using AC_PATH_PROG as Helmut suggested.
Nothing complicated about it. Simple 'make'. Tested with --host=gcc-arm-linux-gnueabihf which generates libdwarf as arm fine, but the dwarfdump final link fails because AC_TRY_COMPILE looks for -lz and looks in the build machine location, not the cross area. Because the cross area does not have -lz, while the build environment does I need to find out at build time about that target library. I'm not sure how to fix this part, cannot find anything on the web but words admitting it is a problem. Pushed this stuff to sourceforge so it at least actually builds libdwarf and gets dwarfdump objects built though the final link fails on the -lz issue. Any suggestions to detect -lz in the target libraries? David Anderson
