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At 12:12 PM 6/14/2001, J. Johnston wrote: >Frank Wuebbeling wrote: > > > > Hi, > > > > > Newlib changed math.h in January to have an errno-like solution for > > signgam whereby a function gets > > > called. Is math.h up to date in the user's Cygwin and is it being > > included by the source code in > > > question? > > > > Ok. The change to math.h produces my problem, I think. I have a fairly > > recent system, that has been updated using cygwin's setup last week. I'll > > try to illustrate my problem. Here's the shortest code I can come up with: > > > > #include "math.h" > > main() > > { > > double a=signgam; > > } > > > > Use "cc x.c -lm" to compile it. Works without problems on LINUX, for > > example. CYGWIN, in the version I have, gives: > > > > wuebbel% cc x.c -lm > > /c/FENSTER/TEMP/ccKdCoNl.o(.text+0xc):x.c: undefined reference to > > `__signgam' > > collect2: ld returned 1 exit status > > > >Ok, Frank, I know the problem. Add -lc to your compile. The signgam function was placed in the >libc library, not libm. > >-- Jeff J. For Cygwin, that's not the problem. libm == libc == libcygwin. Since libcygwin is linked by default, there is no need to specify any of these really. So the problem and solution is as Frank subsequently describes it. > > That's because *my* math.h contains the lines: > > > > #ifndef _REENT_ONLY > > #define signgam (*__signgam()) > > extern int *__signgam _PARAMS((void)); > > #endif /* ! defined (_REENT_ONLY) */ > > > > ...but __signgam is never defined anywhere in the math library. The posting > > I referred to recommended replacing the lines in question in math.h by > > > > extern __IMPORT struct _reent reent_data; > > #define signgam reent_data._new._reent._gamma_signgam > > > > which solved my problem. If my math.h is old, then for some reason it's not > > updated by the cygwin setup. > > <snip> Larry Hall lhall AT rfk DOT com RFK Partners, Inc. http://www.rfk.com 118 Washington Street (508) 893-9779 - RFK Office Holliston, MA 01746 (508) 893-9889 - FAX -- Want to unsubscribe from this list? Check out: http://cygwin.com/ml/#unsubscribe-simple
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