other/1032: Building gcc-2.95.2 on AIX 4.1.5.0 proceeds without finding cpp

[isisx2 at intex dot com]

>Number:         1032
>Category:       other
>Synopsis:       Building gcc-2.95.2 on AIX 4.1.5.0 proceeds without finding cpp
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Dec 10 14:56:00 PST 2000
>Closed-Date:
>Last-Modified:
>Originator:     Daniel Melnechuk
>Release:        gcc version 2.95.2 19991024 (release)
>Organization:
>Environment:
powerpc-ibm-aix4.1.5.0
>Description:
During the configuration stage of building gcc-2.95.2, the
config script barfed on locating the c preprocessor and left
it set to the default of '/lib/cpp'. The results were that
many, if not most, of the configuration thought there were
no include files, nor many system calls. This made itself
evident when running 'make bootstrap' as conflicts between
macros showed up, etc.

Once i finally diagnosed the problem as above, i make a
symlink from '/lib/cpp' to the real cpp that was:

	/usr/vac/exe/xlCcpp

Hope this helps the next builder on 4.1.5.0.
>How-To-Repeat:
Try a fresh clean config and build.
>Fix:
In "gcc/configure", there is some code that checks to see
how to call the c preprocessor. The first line of the code
has an echo command with the followling text on it.

	"checking how to run the C preprocessor"

To be blunt, i did not fix the script. I instead, as stated
above, just made the wrongly guessed location of /lib/cpp
be a symlink to the correct cpp.

I have not studied the code clearly, but i think that the
gcc/configure script is failing all the tests for locating 
a cpp and is then just using /lib/cpp and not testing if
that is correct. This should be fixed to report that it can
not find a cpp and should stop the configure since configure
is SO dependent on cpp.
>Release-Note:
>Audit-Trail:
>Unformatted: