bug#22337: Breakage on amd64 when built with -O1 and higher

[Andreas Metzler <ametzler@bebt.de>]

On 2016-01-09 Ludovic Courtès <ludo@gnu.org> wrote:
> Andreas Metzler <ametzler@bebt.de> skribis:

> > Debian used to build guile-2.0 without optimization, after changing to
> > -O2 random segfaults in guile-gnutls testsuite started to appear on
> > amd64.

> Are you sure the GnuTLS issue has anything to do with that?

> Guile has always been built with ‘-O2 -g’ by default, and building with
> ‘-O0’ has never really been supported (the VM engine could eat too much
> stack space and do silly things.)

Hello,

Yes, I have now built guile more than a dozen times.

And I have just doublechecked again, comparing builds of

http://snapshot.debian.org/archive/debian/20141008T040958Z/pool/main/g/guile-2.0/guile-2.0_2.0.11%2B1-9.dsc
and
http://snapshot.debian.org/archive/debian/20150906T035304Z/pool/main/g/guile-2.0/guile-2.0_2.0.11%2B1-10.dsc
:

buildlog.guile-2.0_2.0.11+1-9_amd64:
make[1]: Leaving directory '/tmp/GUILE/guile-2.0-2.0.11+1-9'
   dh_auto_build -O--parallel
	make -j5
make[1]: Entering directory '/tmp/GUILE/guile-2.0-2.0.11+1-9'
make -C libguile scmconfig.h
make[2]: Entering directory '/tmp/GUILE/guile-2.0-2.0.11+1-9/libguile'
\
if [ "no" = "yes" ]; then \
	gcc -DHAVE_CONFIG_H  -I.. \
	   -c -o gen-scmconfig.o gen-scmconfig.c; \
else \
	gcc -DHAVE_CONFIG_H   -DBUILDING_LIBGUILE=1 -I.. -I.. -I../lib -I../lib  -I/tmp/GUILE/guile-2.0-2.0.11+1-9 -Wdate-time -D_FORTIFY_SOURCE=2 -Wall -Wmissing-prototypes -Wdeclaration-after-statement -Wpointer-arith -Wswitch-enum -fno-strict-aliasing -fwrapv -fvisibility=hidden -DPACKAGE_PACKAGER='"Debian"' -DPACKAGE_PACKAGER_VERSION='"2.0.11-deb+1-9"' -DPACKAGE_PACKAGER_BUG_REPORTS='"http://www.debian.org/Bugs/Reporting"' -c -o gen-scmconfig.o gen-scmconfig.c; \
fi
\

buildlog.guile-2.0_2.0.11+1-10_amd64
   dh_auto_build -O--parallel
	make -j5
make[1]: Entering directory '/tmp/GUILE/guile-2.0-2.0.11+1-10'
make -C libguile scmconfig.h
make[2]: Entering directory '/tmp/GUILE/guile-2.0-2.0.11+1-10/libguile'
\
if [ "no" = "yes" ]; then \
	gcc -DHAVE_CONFIG_H  -I.. \
	   -c -o gen-scmconfig.o gen-scmconfig.c; \
else \
	gcc -DHAVE_CONFIG_H   -DBUILDING_LIBGUILE=1 -I.. -I.. -I../lib -I../lib  -I/tmp/GUILE/guile-2.0-2.0.11+1-10 -Wdate-time -D_FORTIFY_SOURCE=2 -Wall -Wmissing-prototypes -Wdeclaration-after-statement -Wpointer-arith -Wswitch-enum -fno-strict-aliasing -fwrapv -fvisibility=hidden -g -O2 -fstack-protector-strong -Wformat -Werror=format-security -DPACKAGE_PACKAGER='"Debian"' -DPACKAGE_PACKAGER_VERSION='"2.0.11-deb+1-10"' -DPACKAGE_PACKAGER_BUG_REPORTS='"http://www.debian.org/Bugs/Reporting"' -c -o gen-scmconfig.o gen-scmconfig.c; \
fi

As you can see the former has no -Ox option, the latter has -O2. The
old debian/rules was buggy.
Downgrade guile to 2.0.11+1-9 from snapshots and the issue goes away.

cu Andreas

-- 
`What a good friend you are to him, Dr. Maturin. His other friends are
so grateful to you.'
`I sew his ears on from time to time, sure'