Hi Phillip Great. Thanks a ton for your mail and solution. I will try as you had suggested. Since this mail was posted, I have now moved to gcc 4.5.1 skipped 4.5.0 altogether. It is nice to know that you had the same issue on 4.5.1 and will try your suggestion in that. I will send an update soon. With Regards Vardhan -----Original Message----- From: Philipp Edelmann [mailto:edelmann@xxxxxxxxxxxxxxxxxxx] Sent: Tuesday, August 10, 2010 4:39 AM To: Vardhan, Sundara (GE Energy) Cc: gcc-help@xxxxxxxxxxx Subject: Re: GCC 4.5.0 - libgfortran issue Dear Vardhan, On Tue, May 18, 2010 at 08:21:21AM -0400, Vardhan, Sundara (GE Infra, Energy) wrote: > I downloaded the GCC 4.5.0 source and am compiling on AIX 6.1. The > following is the configure command used to build the make files etc > > /cots/gnu/gcc-4.5.0/configure --with-as=/usr/bin/as > --with-ld=/usr/bin/ld --enable-languages=c,c++,fortran > --prefix=/cots/gnu/gcc450 --enable-threads --disable-nls > --enable-decimal-float=dpd --with-mpfr=/cots/gnu/mpfr242 > --with-gmp=/cots/gnu/gmp501 --with-mpc=/cots/gnu/mpc081 > > Set the CONFIG_SHELL to bash and when compiled I get the following > error > : > > ld: 0711-317 ERROR: Undefined symbol: .__copysignl128 > ld: 0711-317 ERROR: Undefined symbol: .__nextafterl128 > ld: 0711-317 ERROR: Undefined symbol: .__scalbnl128 > ld: 0711-317 ERROR: Undefined symbol: .__cabsl128 > ld: 0711-317 ERROR: Undefined symbol: .__cargl128 > ld: 0711-317 ERROR: Undefined symbol: .__truncl128 > ld: 0711-345 Use the -bloadmap or -bnoquiet option to obtain more > information. > collect2: ld returned 8 exit status > make[3]: *** [libgfortran.la] Error 1 > make[3]: Leaving directory > `/cots/gnu/build450/powerpc-ibm-aix6.1.4.0/libgfortran' I encountered the same problem while compiling gcc-4.5.1 on AIX. The problem is that GCC tries to use the 128 bit long double functions. These are not the default on AIX (see [1]). I tried to find the library comprising the missing functions but I could not find it. A quick and dirty solution is to undefine the macro __LONGDOUBLE128, which causes the compiler to use the normal long double functions instead of the 128 bit variants. I am not sure what happens to quad precision Fortran calculations in this case, you should definitely check that first. I attached a patch that fixes compilation for me. I would be glad to hear if were successful with it. Also a GCC developer could maybe comment on a real solution to the problem. It seems that only some of the 128 bit functions are missing (or I just didn't find them with find and objdump), so we need a replacement. Anyway, the 128 bit floats on AIX are not IEEE 754 compliant (they are just two normal 64 bit floats that are added to yield a larger mantissa), so I am not sure if it actually makes sense to use those functions when strict floating point behavior is required. Cheers, [1] http://publib.boulder.ibm.com/infocenter/aix/v6r1/index.jsp?topic=/com.i bm.aix.genprogc/doc/genprogc/128bit_long_double_floating-point_datatype. htm -- Philipp Edelmann Max Planck Institute for Astrophysics Tel. +49-89-30000-2272
