My first post here, so please bear with me if this question falls short of the mark. I have been working on GHDL, the VHDL front end, which used to build against gcc4.4 or so around 2010, but stopped building against newer gcc versions. I've mostly brought it up to date against gcc4.7.2 and working well, and the best of my changes (and other cleanups) have been accepted into mainstream GHDL by Tristan Gingold, the original author. But there's one problem where my workaround was not accepted : a clash between a GHDL cmdline option, -P<library_path> and another use, namely "-P : Inhibit generation of linemarkers in the output from the preprocessor." My workaround was to rename the GHDL one to -LP but that involves unpleasant changes to existing user's build scripts. A better one would be to allow the two uses to peacefully coexist. This was the case until gcc4.4 or later since neither -P option is new. But something seems to have changed in the command line parsing strategy since then; I am looking for some idea what changed, and how to modify GHDL to fit in with that strategy. So, what mechanism is supposed to route -P<dir> to ghdl or ghdl1, and -P alone to the other compilers, and how (in the GHDL front end) could it be broken? The following four functions in the ghdl interface (in ortho-lang.c) look significant, and are hooked into LANG_HOOKS but that's the extent of my knowledge. static unsigned int ortho_option_lang_mask (void) static bool ortho_post_options (const char **pfilename) extern bool lang_handle_option (const char *opt, const char *arg); static bool ortho_handle_option (...) Rather than ask "please fix it for me" I would ask, "where should I look, what should I be reading, which front end should I be studying?" to resolve the name clash in a bentter way. I have found the GCC internals description of the lang.opt file format, but not much else. Thanks, - Brian Relevant section of vhdl/lang.opt: ----------------------------------------------------- P vhdl Joined -P<dir> Add <dir> to the end of the vhdl library path ----------------------------------------------------- Symptoms of clash: Failure of second stage build, in libstdc++, at the following point, with "xgcc: error: missing argument to ‘-P’" ----------------------------------------------------- /home/brian/Projects/ghdl/build472/./gcc/xgcc -B/home/brian/Projects/ghdl/build472/./gcc/ -B/usr/local/ghdl/x86_64-unknown-linux-gnu/bin/ -B/usr/local/ghdl/x86_64-unknown-linux-gnu/lib/ -isystem /usr/local/ghdl/x86_64-unknown-linux-gnu/include -isystem /usr/local/ghdl/x86_64-unknown-linux-gnu/sys-include -E -P -include ../config.h - > libstdc++-symbols.ver || (rm -f libstdc ++-symbols.ver ; exit 1) xgcc: error: missing argument to ‘-P’ make[5]: *** [libstdc++-symbols.ver] Error 1 make[5]: Leaving directory `/home/brian/Projects/ghdl/build472/x86_64-unknown-linux-gnu/libstdc ++-v3/src' -----------------------------------------------------
