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Re: What is libg2c.a? And why do I have to link to it?

Mikael> I have a autoconf test that fails if i don't give -lg2c as
Mikael> extra link flags.  Without g2c there are undefined references
Mikael> to e_wsfe, z_abs, c_sqrt, etc.  Is not g2c an internal gcc
Mikael> thing?

dnl this fails for lapack
AC_CHECK_LIB(m, pow)

dnl this succeeds for lapack
AC_CHECK_LIB(m, pow)

The blas and lapack libraries are originally written in Fortran, I
believe.  Thus gcc needs the Fortran compatibility library g2c when
linking them. (The g in the name stands for g77, not very obvious

Ian Zimmerman, Oakland, California, U.S.A.
GPG: 433BA087  9C0F 194F 203A 63F7 B1B8  6E5A 8CA3 27DB 433B A087
EngSoc adopts market economy: cheap is wasteful, efficient is expensive.

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