Re: compiling GSL on digital unix.

[Brian Gough <bjg at network-theory dot co dot uk>]

Thanks for the bug report. I've passed your message on to Tim Mooney
who has provided the alpha IEEE support.  I believe the -mieee flag
enables support for floating point exception handling. As you say, it
isn't mentioned in the documentation for gcc-2.7.2 -- so it may be a
feature of later versions of gcc only.

Apart from the functions to set the exception handlers in the
ieee-utils/ directory the rest of GSL won't be affected.

Jon McAuliffe writes:
 > 
 > hi,
 > 
 > i'm compiling gsl-0.4.1 on digital unix v4.0e, rev. 1091, using gcc-2.7.2.3.
 > i ran configure successfully. fyi, here is the system type it identified:
 > 
 > checking host system type... alphaev56-dec-osf4.0e
 > 
 > when i ran make, i received the following output:
 > 
 > host:~/gsl-0.4.1 [49] make
 > make all-recursive
 > make[1]: Entering directory `/home3/jonm/gsl-0.4.1'
 > Making all in err
 > make[2]: Entering directory `/home3/jonm/gsl-0.4.1/err'
 > gcc -DHAVE_CONFIG_H -I. -I. -I..   -mieee -g -O2 -c error.c
 > cc1: Invalid option `ieee'
 > make[2]: *** [error.o] Error 1
 > make[2]: Leaving directory `/home3/jonm/gsl-0.4.1/err'
 > make[1]: *** [all-recursive] Error 1
 > make[1]: Leaving directory `/home3/jonm/gsl-0.4.1'
 > make: *** [all-recursive-am] Error 2
 > 
 > i poked around the Info node for gcc, trying to find documentation on -mieee.
 > no luck. i then made the following change to configure:
 > 
 > host:~/gsl-0.4.1 [51] diff configure.ORIG configure
 > 2210,2213d2209
 > <         alpha*-*-*) 
 > <             CFLAGS="-mieee $CFLAGS"
 > <             echo "$ac_t""adding -mieee" 1>&6
 > <             ;;
 > 
 > this change suppresses the addition of the -mieee flag for alpha machines.
 > i re-ran configure, then successfully built libgsl.a.
 > 
 > two questions:
 > 
 > 1. what is -mieee? it is not a documented part of the gcc i am using.
 > 
 > 2. am i going to get incorrect behavior out of libgsl.a by virtue of
 >    the absence of this architecture-dependent compile flag?
 > 
 > thanks
 > jon.
 > 
 > 
 >