Re: other/1512: Path confusion w/ -print-prog-name + autoconf

[Nathan Neulinger <nneul at umr dot edu>]

The following reply was made to PR other/1512; it has been noted by GNATS.

From: Nathan Neulinger <nneul@umr.edu>
To: bangerth@dealii.org, gcc-bugs@gcc.gnu.org, gcc-prs@gcc.gnu.org,  nobody@gcc.gnu.org, gcc-gnats@gcc.gnu.org
Cc:  
Subject: Re: other/1512: Path confusion w/ -print-prog-name + autoconf
Date: 05 Dec 2002 21:43:51 -0600

 On Thu, 2002-12-05 at 14:01, bangerth@dealii.org wrote:
 > Synopsis: Path confusion w/ -print-prog-name + autoconf
 > 
 > State-Changed-From-To: open->feedback
 > State-Changed-By: bangerth
 > State-Changed-When: Thu Dec  5 12:01:11 2002
 > State-Changed-Why:
 >     This is a rather old report. I don't think I understand the
 >     issue properly from the description, but would like to ask
 >     anyway whether the problem still exists in present versions
 >     of gcc?
 >     
 >     Thanks
 >       Wolfgang
 > 
 > http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=1512
 
 Don't know. I am still using the workaround I'm came up with when I
 submitted that report. However, you ask at an opportune time - as I'll
 probably be trying to install the version you just released soon, and
 can try installing it without the workaround and test.
 
 To more clearly explain the issue:
 
 I install products via a set of link trees. To get to the resulting
 binary, several links are traversed. The resulting path of the
 executable winds up with ..'s in it due to the way gcc is choosing to
 generate the paths to installation dirs.
 
 i.e.:
 
 /umr/devbin/../lib/gcc-lib/i686-pc-linux-gnu/2.97/../../../../i686-pc-linux-gnu/bin/ld
 
 That path, when processed as a whole, is valid. Problem is, autoconf
 appears to be compacting down the ..'s itself improperly or something. 
 
 Short explanation:
 
 /umr/devbin points to /afs/....../trees/.../bin
 
 /umr/devbin/../lib points to /afs/....../trees/.../lib
 
 problem is, autoconf is seemingly turning that into
 
 
 checking for ld used by GCC... (cached) /umr/i686-pc-linux-gnu/bin/ld
 checking if the linker (/umr/i686-pc-linux-gnu/bin/ld) is GNU ld...
 (cached) no
 
 
 It's removing the ..'s by stripping off pairs of .. and dirname. That
 would be fine if they were all REALLY dirs. i.e.
 
 /umr/devbin/../lib == /umr/lib IFF /umr, /umr/devbin are DIRS
 /umr/devbin/../lib != /umr/lib IF /umr/devbin is a symlink. 
 
 
 It's really an autoconf macro problem with how it is processing the ..'s
 in path improperly, however, it would be mitigated by having gcc return
 a less ..-happy path. 
 
 Please let me know if I can explain this further. I'll let you know if
 it is still an issue with the version y'all just released when I get it
 installed.
 
 -- Nathan
 
 ------------------------------------------------------------
 Nathan Neulinger                       EMail:  nneul@umr.edu
 University of Missouri - Rolla         Phone: (573) 341-4841
 Computing Services                       Fax: (573) 341-4216