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

["sgk at troutmask dot apl.washington.edu" <gcc-bugzilla at gcc dot gnu dot org>]

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

--- Comment #4 from Steve Kargl <sgk at troutmask dot apl.washington.edu> 2011-08-03 19:09:22 UTC ---
On Wed, Aug 03, 2011 at 07:01:55PM +0000, jimis at gmx dot net wrote:
> 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.

Have you actually read the instead instructions for gcc?
Have you tried the documented method [*]:

make DESTDIR=path-to-rootdir install

[*] I don't know if it works.  If it fails, then you have
    bug to report.