RE: Your commits (cont'd)

[Ralph Lange <Ralph.Lange@mail.bessy.de>]

Jeff,

  > Was this problem occurring with R3.14.Beta2? I guess not.

I used the term "your latest commits" to describe the moment when these
errors occurred first.

  > [...] If necessary I will install gcc 2.95 into one of our Linux
  > systems to test further. Do you know if it's safe to use a gcc
  > version on Linux which significantly varies from the gcc version
  > that was used to build the Linux kernel?

The only problem is the mysterious 2.96 that RedHat shipped with their
distribution < 8.0 (now they're using gcc 3), which is based on an
unofficial snapshot from GNU that was never meant to be released plus
further bugfixes by RedHat.

The RedHat version's c++ name mangling is incompatible with any gcc 2 as
well as with any gcc 3. So you cannot use _static_ RedHat system
libraries for linking code produced by any other compiler version.

Shared libs / dynamically linked binaries are working without any
problems. I'm using 2.95.3 on my RedHat system for anything except
kernel compilation since ever without any failure.

Actually, I installed a variety of gcc versions on my RedHat box, put
them all in /opt/gcc-<version> directories and can easily switch by
setting the GNU_DIR in the configure files. Just build the gcc from
sources with "./configure --prefix=/opt/gcc-<version" and make/install.

You will also need to build a recent version of the binutils package and
re-install it (using the same configure command line) into every of
these gcc directories. Re-installing will do - no need to recompile.

That's it. (You may need to update /etc/ld.so.conf and 'ldconfig'.)

Ralph

  >> -----Original Message-----
  >> From: Ralph Lange [mailto:Ralph.Lange@mail.bessy.de]
  >> Sent: Monday, November 04, 2002 2:07 AM
  >> To: Jeff Hill
  >> Cc: Bob Dalesio; Andrew Johnson; Kay-Uwe Kasemir;
  > timo.korhonen@psi.ch;
  >> Marty Kraimer; eric.norum@usask.ca
  >> Subject: Your commits (cont'd)
  >> 
  >> >>>>> "Ralph" == Ralph Lange <Ralph.Lange@mail.bessy.de> writes:
  >> 
  >> > Hi Jeff,
  >> > when I'm compiling your latest commits on my Linux box (RedHat 7.1
  >> with
  >> > g++ 2.95.3) I get
  >> 
  >> > /opt/gcc/bin/g++ -c   -D_POSIX_C_SOURCE=199506L -D_POSIX_THREADS
  > -
  >> DOSITHREAD_USE_DEFAULT_STACK       -D_X86_  -DUNIX  -D_BSD_SOURCE -
  >> Dlinux  -D_REENTRANT -ansi -pedantic  -O3  -Wall       -mcpu=pentium -
  >> fPIC    -I. -I.. -I../../../include/os/Linux -
  >> I../../../include          ../cac.cpp
  >> > In file included from ../virtualCircuit.h:35,
  >> >                  from ../cac.cpp:37:
  >> > ../comQueSend.h: In method `void
  > comQueSend::push<ca_uint16_t>(const
  >> ca_uint16_t &)':
  >> > ../comQueSend.h:145:   instantiated from here
  >> > ../comQueSend.h:123: Internal compiler error.
  >> > ../comQueSend.h:123: Please submit a full bug report.
  >> > ../comQueSend.h:123: See
  >> <URL:http://www.gnu.org/software/gcc/bugs.html> for instructions.
  >> > make[3]: *** [cac.o] Error 1
  >> 
  >> 
  >> Hm.
  >> 
  >> Same error using gcc 2.95.4.
  >> The RedHat original (yuck) so-called gcc 2.96 works.
  >> Version 3 gcc seems to work, too.
  >> 
  >> What should we do? Which gcc versions are we officially supporting?
  >> (Didn't find anything on the EPICS web.)
  >> 
  >> Cheers,
  >> Ralph