internal compiler error: in fixup_reorder_chain,, at cfgrtl.c:3336

[Ming Lei]

When building samba package on trusty/arm64 with gcc-4.8, the following build crash can be observed, and it can be triggered with gcc-4.7 too.

01:07:10 runner /usr/bin/gcc -g -O2 -fstack-protector --param=ssp-buffer-size=4
-Wformat -Werror=format-security -fPIC -D_REENTRANT
-D_POSIX_PTHREAD_SEMANTICS --
DSTATIC_LOCKING_MODULES=NULL -DSTATIC_LOCKING_MODULES_PROTO=extern
void __LOCKINN
G_dummy_module_proto(void) -MD -D_FORTIFY_SOURCE=2 -Idefault/source3
-I../sourcee
3 -Idefault/source3/include -I../source3/include -Idefault/source3/lib
-I../sourr
ce3/lib -Idefault/source4/heimdal/lib/com_err
-I../source4/heimdal/lib/com_err --
Idefault/source4/heimdal/lib/krb5 -I../source4/heimdal/lib/krb5
-Idefault/sourcee
4/heimdal/lib/gssapi -I../source4/heimdal/lib/gssapi
-Idefault/source4/heimdal_bb
uild -I../source4/heimdal_build
-Idefault/bin/default/source4/heimdal/lib/asn1 --
Idefault/source4/heimdal/lib/asn1 -Idefault/include/public
-I../include/public --
Idefault/source4 -I../source4 -Idefault/lib -I../lib
-Idefault/source4/lib -I..//
source4/lib -Idefault/source4/include -I../source4/include
-Idefault/include -I..
./include -Idefault/lib/replace -I../lib/replace -Idefault -I..
-Idefault/librpcc
 -I../librpc -Idefault/libcli/security -I../libcli/security
-Idefault/source3/lii
brpc -I../source3/librpc -Idefault/libcli/util -I../libcli/util
-Idefault/lib/utt
il/charset -I../lib/util/charset -Idefault/dynconfig -I../dynconfig
-Idefault/lii
b/compression -I../lib/compression -Idefault/libcli/nbt
-I../libcli/nbt -Idefaull
t/lib/crypto -I../lib/crypto -I/usr/local/include -D_SAMBA_BUILD_=4
-DHAVE_CONFII
G_H=1 -D_GNU_SOURCE=1 -D_XOPEN_SOURCE_EXTENDED=1 ../source3/locking/brlock.c -c
-o default/source3/locking/brlock_92.o
../source3/smbd/notify.c: In function ‘change_notify_create’:
../source3/smbd/notify.c:297:1: internal compiler error: in
fixup_reorder_chain,,
 at cfgrtl.c:3336
../source3/smbd/notify.c: In function ‘change_notify_create’:
../source3/smbd/notify.c:297:1: internal compiler error: in
fixup_reorder_chain,,
 at cfgrtl.c:3336
 }
 ^
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-4.8/README.Bugs> for instructions.

[Ming Lei (tom-leiming)]

Follos the steps to reproduce the issue:

1, find a arm64 machine or VM, which is installed trusty

2, prepare for building samba:
sudo apt-get -y install dpkg-dev fakeroot
sudo apt-get -y build-dep samba

3, download the following samba source:
wget https://launchpad.net/ubuntu/+archive/primary/+files/samba_4.3.9+dfsg.orig.tar.xz
wget https://launchpad.net/ubuntu/+archive/primary/+files/samba_4.3.9+dfsg-0ubuntu0.14.04.1.debian.tar.gz
wget https://launchpad.net/ubuntu/+archive/primary/+files/samba_4.3.9+dfsg-0ubuntu0.14.04.1.dsc

4, start the building:

dpkg-source -x samba_4.3.9+dfsg-0ubunntu0.14.04.1.dsc
cd samba-4.3.9+dfsg
fakeroot debian/rules clean;
CONCURRENCY_LEVEL=`getconf _NPROCESSORS_ONLN` fakeroot debian/rules binary

5, then the gcc crash can be observed

Thanks,

[Steve Langasek (vorlon)]

Hi Tom,

Can you please help us isolate a reduced test case for this issue, preferably with a single preprocessed source file and a minimal set of gcc flags necessary to reproduce it?

[Ming Lei (tom-leiming)]

Please see the gcc-4.8 crash log on trusty/arm64, which includes the gcc flag and PreprocessedSource.

[Matthias Klose (doko)]

workaround is to build the file with -fno-if-conversion.

[Matthias Klose (doko)]

$ cat notify.i
_Bool a;
fn1(unsigned int p1) {
  unsigned int b = a ? p1 : 0;
  if (p1 || b)
    fn2(0, p1, b);
}
$ gcc -c -O1 -fno-if-conversion notify.i
$ gcc -c -O1 notify.i
notify.i: In function 'fn1':
notify.i:6:1: internal compiler error: in fixup_reorder_chain, at cfgrtl.c:3336
 }
 ^
Please submit a full bug report,
with preprocessed source if appropriate.

still seen in 4.8.5 (16.04), doesn't show in 4.9 (and gcc-snapshot in trusty)

[Andrew Cloke (andrew-cloke)]

I've raised https://bugs.launchpad.net/ubuntu/+source/samba/+bug/1585174 to highlight the issue and suggest using the "-fno-if-conversion" option that Matthias has identifed.