[Bug libfortran/49970] "make prefix=... install" doesn't work

["jimis at gmx dot net" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49970

--- Comment #2 from jimis <jimis at gmx dot net> 2011-08-03 19:01:51 UTC ---
I use it casually for packages that use autotools to configure the build, it
always works fine. And for gcc it has worked for me plenty of times for i386
C-frontend only builds, and till not I've only seen libgfortran failing.

Why it should be supported? Especially for GCC it is very handy, I build the
beast without configuring --prefix at all, and then install someplace. Then I
apply some patch, hit make and only relevant files are compiled, and install
some place elsewhere. If I had to reconfigure with a different --prefix, make
would build many more files, and I'd have to delete various config.cache files
because I reconfigured.

Quote from automake manual: 

All these directory variables have values that start with either â${prefix}â or
â${exec_prefix}â unexpanded. This works fine in Makefiles, but it makes these
variables hard to use in configure. This is mandated by the GNU coding
standards, so that the user can run âmake prefix=/foo installâ. The Autoconf
manual has a section with more details on this topic (see Installation
Directory Variables). See also Hard-Coded Install Paths.