On 23.09.2010, at 10:13, MacArthur, Ian (SELEX GALILEO, UK) wrote: > >> I notice there are a lot of warning messages when compiling FLTK >> >> Things like : >> >> :/mingw/bin/../lib/gcc/mingw32/4.5.0/../../../../mingw32/bin/l >> d.exe: warning: a >> to-importing has been activated without --enable-auto-import >> specified on the cmmand line. >> This should work unless it involves constant data structures >> referencing symbols > > Hmm, don't think I've seen that one. Not even sure what it means though! > Are you building a static lib or a DLL BTW? > > Note that the more recent versions of gcc have become very verbose as > they keep ramping up the warning levels... > Usually it doesn't mean anything!
I've seen this too with a recent MinGW32/MSYS installation with gcc 4.5. ISTR that it has something to do with "weak symbols" in dll's and with the (shareable) C++ runtime (don't know exactly, though). IIRC the changes enable among others to throw exceptions between different dll's (that may not have worked otherwise). But I may also be completely wrong here... This warning *can* get you troubles, and IIRC my first build didn't work until I added -Wl,--enable-auto-import to the linker options (fluid crashed otherwise, maybe, when converting the .fl files). But I didn't investigate this further, and I don't know yet if it's okay to set this option or if it can have other side effects. At least here's a workaround: add -Wl,--enable-auto-import >> Warnings about&& and || too > > Yup - that's "normal" for gcc 4.5.x since they added the extra warnings. > It does not appear that the fltk code is wrong, but "they" want us to > put in more () to make the binding explicit. > And no one has had the time to edit just about every file to add the > extra braces... > Of course, if it's an itch you feel the need to scratch, then patches > are always welcome! Well, we *have* a patch, and I think that it is so far okay, but I'd like to have someone else check it. Ian, Greg, could you maybe take a look at it? There are two different patches in STR 2405. Any comments welcome. I'd like to commit the patches, but not before the next monday, so there's some time left to comment... ;-) http://www.fltk.org/str.php?L2405 http://www.fltk.org/strfiles/2405/gcc-4.3.2_file1_v2.patch http://www.fltk.org/strfiles/2405/gcc-4.3.2_file2.patch Both patches are independent, and if you can't find any errors, I'd appreciate your comments. Just looking over them if there's something obvious that I missed would suffice. TIA >> I presume this wont produce unanticipated side-effects when >> using FTLK ? I don't know about the first (auto-import, linker) problem for sure, but the other warnings are benign. > Has always worked just fine for me (for whatever that may be worth, of > course!) Yep, for me, too, but I didn't test enough with the new MinGW32 tools to know for sure, and I won't be able to do this for the next few days... :-( Side note (to Ian): I'm sharing your experience WRT Cygwin/MinGW, and I'm in a process to switch over to using MinGW for production, because the current Cygwin development doesn't seem usable w/o too much pain any more. BTW: which subversion tools are you using? I'm still using Cygwin's svn and didn't see a MinGW version yet, and I don't want to build my own because of the dependencies. Any suggestions? Albrecht _______________________________________________ fltk-dev mailing list [email protected] http://lists.easysw.com/mailman/listinfo/fltk-dev
