[patch] Add toplevel configure check for MPFR

[Paul Brook]

On Sunday 25 July 2004 16:52, Joseph S. Myers wrote:
> On Sun, 25 Jul 2004, Paul Brook wrote:
> > Gfortran currently requires GMP (GNU Multiple Precision library) for
> > compile-time arithmetic. In order to accurately match target arithmetic
> > we also require MPFR. MPFR is part of GMP, although it is not always
> > enabled.
>
> Note also that the GMP home page <http://www.swox.com/gmp/> says that "In
> the next major GMP release, mpfr will not be included.  Users are
> encouraged to download mpfr directly from that project's site.".  

Oh, ok. The MPFR project website says:

"The MPFR library [...] is based on the GMP multiple-precision library and 
should replace the MPF class in further releases of GMP."

I assumed this meant it would be included in GMP.

How about the following?

Paul

Index: install.texi
===================================================================
RCS file: /var/cvsroot/gcc-cvs/gcc/gcc/doc/install.texi,v
retrieving revision 1.299
diff -u -p -r1.299 install.texi
--- install.texi	20 Jul 2004 19:52:11 -0000	1.299
+++ install.texi	25 Jul 2004 16:57:45 -0000
@@ -291,6 +291,15 @@ Necessary to build the Fortran frontend.
 installed in your library search path, you will have to configure with
 the @option{--with-gmp} or @option{--with-gmp-dir} configure option.
 
+@item MPFR Library
+
+Necessary to build the Fortran frontend.  It can be downloaded from
+@uref{http://http://www.mpfr.org/}.  It is also included in the current GMP
+release (4.1.3) when configures with @option{--enable-mpfr}.
+
+The @option{--with-gmp} or @option{--with-gmp-dir} configure option should
+be used if the MPFR Library is not installed in you library search path.
+
 @end table
 
 
@@ -1205,9 +1214,9 @@ The following options apply to the build
 
 @item --with-gmp=@var{pathname}
 @itemx --with-gmp-dir=@var{pathname}
-If you don't have GMP (the GNU Multiple Precision library) installed
-in a standard location and you want to build the Fortran front-end,
-you can explicitly specify the directory where GMP is installed
+If you don't have GMP (the GNU Multiple Precision library) and the MPFR 
+Library installed in a standard location and you want to build the Fortran
+front-end, you can explicitly specify the directory where they are installed
 (@samp{--with-gmp=gmpinstalldir}) or where you built the GMP library without
 installing (@samp{--with-gmp-dir=gmpbuilddir}).