Re: can't find ceil function in math library

2014-07-03 Thread ingo . krabbe
> hi: > I have a configure.ac file includes: AC_CHECK_LIB([m], [ceil]) > then I got this result: checking for ceil in -lm... no > but a .c file contains ceil function works very well with or without -lm, > why is that? > > libtool version: 2.4.2 > system: Ubuntu 13.04 Most likely cleil is no fu

Re: can't find ceil function in math library

2014-07-03 Thread ingo . krabbe
> hi: > I have a configure.ac file includes: AC_CHECK_LIB([m], [ceil]) > then I got this result: checking for ceil in -lm... no > but a .c file contains ceil function works very well with or without -lm, > why is that? > > libtool version: 2.4.2 > system: Ubuntu 13.04 Most likely cleil is no fu

Re: can't find ceil function in math library

2014-07-03 Thread ingo . krabbe
> hi: > I have a configure.ac file includes: AC_CHECK_LIB([m], [ceil]) > then I got this result: checking for ceil in -lm... no > but a .c file contains ceil function works very well with or without -lm, > why is that? > > libtool version: 2.4.2 > system: Ubuntu 13.04 Most likely cleil is no fu

Re: can't find ceil function in math library

2014-07-03 Thread Ingo Krabbe
Actually it makes not much sense to ask about why autoconf a/o libtool does this or that, as the tools themselves are coded beyond understanding or readability. They just do on some systems what they are expected to do. Of course AC_CHECK_LIB([m],[main]), shouldn't return true as main is no memb

Re: can't find ceil function in math library

2014-07-03 Thread Minxuan Zhuang
I've changed AC_CHECK_LIB([m], [ceil]) to AC_CHECK_LIB([m], [main]) and it works. according to conftest.c, libtool generate a small peace of code to check whether the specific function exists or not. for AC_CHECK_LIB([m], [main]), the code is: main() { return main(); ; return 0; } call

Re: can't find ceil function in math library

2014-07-03 Thread Ingo Krabbe
> hi: > I have a configure.ac file includes: AC_CHECK_LIB([m], [ceil]) > then I got this result: checking for ceil in -lm... no > but a .c file contains ceil function works very well with or without -lm, > why is that? > > libtool version: 2.4.2 > system: Ubuntu 13.04 Most likely cleil is no fu

can't find ceil function in math library

2014-07-03 Thread Minxuan Zhuang
hi: I have a configure.ac file includes: AC_CHECK_LIB([m], [ceil]) then I got this result: checking for ceil in -lm... no but a .c file contains ceil function works very well with or without -lm, why is that? libtool version: 2.4.2 system: Ubuntu 13.04 ___