[Bug lto/55994] New: multiple definition or memset or strlen for builtins tests with LTO options

[Bug lto/55994] New: multiple definition or memset or strlen for builtins tests with LTO options

[janis at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55994

             Bug #: 55994
           Summary: multiple definition or memset or strlen for builtins
                    tests with LTO options
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: janis@gcc.gnu.org
            Target: *-*-eabi or *-elf


I get the following test failures for multiple targets for GCC 4.7 and
mainline:

FAIL: gcc.c-torture/execute/builtins/memcpy-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/memmove-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/memops-asm.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/mempcpy-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/memset-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/memset.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/pr23484-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/snprintf-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/sprintf-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/stpcpy-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/stpncpy-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/strcat-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/strcpy-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/strlen-2.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/strlen-3.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/strlen.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/strncat-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/strncpy-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects
FAIL: gcc.c-torture/execute/builtins/vsnprintf-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects 
FAIL: gcc.c-torture/execute/builtins/vsprintf-chk.c compilation,  -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects

The reported failure is

/tmp/cc3DFMVG.ltrans1.ltrans.o: In function `memset':
cc3DFMVG.ltrans1.o:(.text+0x558): multiple definition of `memset'
/scratch/janisjo/build6/fsf-4.7-arm-eabi/install/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/libc.a(lib_a-memset.o):/scratch/janisjo/build6/fsf-4.7-arm-eabi/src/newlib-mainline/newlib/libc/string/memset.c:57:
first defined here
collect2: error: ld returned 1 exit status

or

/tmp/cc2KdAgP.ltrans0.ltrans.o: In function `strlen':
cc2KdAgP.ltrans0.o:(.text+0x0): multiple definition of `strlen'
/scratch/janisjo/build6/fsf-4.7-arm-eabi/install/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/lib/libc.a(lib_a-strlen.o):/scratch/janisjo/build6/fsf-4.7-arm-eabi/src/newlib-mainline/newlib/libc/machine/arm/strlen.c:68:
first defined here
collect2: error: ld returned 1 exit status

I've seen the failures for arm-none-eabi and powerpc-none-eabi with FSF sources
(the only targets I've tried) and also for CodeSourcery sources for those plus
mips-sde-elf, m68k-elf, and i686-mingw32.  They all use newlib.  The same tests
pass for GNU/Linux targets.

These test options were added for GCC 4.7.

This problem was mentioned in PR54139.

[Bug lto/55994] multiple definition or memset or strlen for builtins tests with LTO options

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55994

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-01-15
     Ever Confirmed|0                           |1

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> 2013-01-15 17:14:25 UTC ---
I think these all fail with a static libc.  Anyways confirmed on
aarch64-thunder-elf and mipsisa64-octeon-elf targets.

[Bug lto/55994] multiple definition or memset or strlen for builtins tests with LTO options

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55994

--- Comment #2 from Uros Bizjak <ubizjak at gmail dot com> 2013-01-15 17:44:20 UTC ---
"-Wl,--allow-multiple-definition" should be appended to additional_flags for
affected targets.

--cut here--
Index: builtins.exp
===================================================================
--- builtins.exp        (revision 195056)
+++ builtins.exp        (working copy)
@@ -40,6 +40,8 @@
 set additional_flags ""
 if [istarget "powerpc-*-darwin*"] {
    lappend additional_flags "-Wl,-multiply_defined,suppress"
+} elseif [istarget "arm-*-*"] {
+   lappend additional_flags "-Wl,--allow-multiple-definition"
 }

 foreach src [lsort [find $srcdir/$subdir *.c]] {
--cut here--

Probably this option should be the default in builtins.exp.

[Bug lto/55994] multiple definition or memset or strlen for builtins tests with LTO options

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55994

--- Comment #3 from Uros Bizjak <ubizjak at gmail dot com> 2013-01-15 17:48:51 UTC ---
Please also read thread at [1].

[1] http://gcc.gnu.org/ml/gcc-help/2011-10/msg00201.html

[Bug testsuite/55994] multiple definition or memset or strlen for builtins tests with LTO options

[janis at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55994

--- Comment #4 from Janis Johnson <janis at gcc dot gnu.org> 2013-01-15 20:00:17 UTC ---
Patch posted: <http://gcc.gnu.org/ml/gcc-patches/2013-01/msg00801.html>.

[Bug testsuite/55994] multiple definition or memset or strlen for builtins tests with LTO options

[janis at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55994

--- Comment #5 from Janis Johnson <janis at gcc dot gnu.org> 2013-01-16 18:52:56 UTC ---
Author: janis
Date: Wed Jan 16 18:52:51 2013
New Revision: 195250

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=195250
Log:
    PR testsuite/55994
    * gcc.c-torture/execute/builtins/builtins.exp: Add
    -Wl,--allow-multiple-definition for eabi and elf targets.

Modified:
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.c-torture/execute/builtins/builtins.exp

[Bug testsuite/55994] multiple definition or memset or strlen for builtins tests with LTO options

[janis at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55994

--- Comment #6 from Janis Johnson <janis at gcc dot gnu.org> 2013-01-25 00:26:43 UTC ---
Author: janis
Date: Fri Jan 25 00:26:34 2013
New Revision: 195458

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=195458
Log:
    Backport from mainline
    2013-01-16  Janis Johnson  <janisjo@codesourcery.com>

    PR testsuite/55994
    * gcc.c-torture/execute/builtins/builtins.exp: Add
    -Wl,--allow-multiple-definition for eabi and elf targets.

Modified:
    branches/gcc-4_7-branch/gcc/testsuite/ChangeLog
   
branches/gcc-4_7-branch/gcc/testsuite/gcc.c-torture/execute/builtins/builtins.exp

[Bug testsuite/55994] multiple definition or memset or strlen for builtins tests with LTO options

[sebastian.huber@embedded-brains.de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55994

Sebastian Huber <sebastian.huber@embedded-brains.de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |sebastian.huber@embedded-br
                   |                            |ains.de

--- Comment #7 from Sebastian Huber <sebastian.huber@embedded-brains.de> 2013-03-20 09:20:24 UTC ---
The crucial thing is also that all these functions are recognized as builtins
and GCC knows what they are expected to do.  The failure also vanishes if
-fno-builtin is used.

Lets have a look at this example:

gcc 1.c 2.c 3.c -l4

I expect that the modules 1.o 2.o 3.o end up in the executable and unresolved
symbols inside this module set are resolved with definitions provided by the
library 4.  In particular if I have a global function f() in 2.c then I expect
to have this function in my executable even in case a global function f() is
also defined in the library 4.

This is wrong for builtins.  Here GCC seems to assume that implementations are
interchangeable.  It would be quite interesting to know what happens if we
compile libc with -flto.

In one failed GCC test f() is memcpy(), 2.c is 20010124-1-lib.c and lib4 is
libc.

[Bug testsuite/55994] multiple definition or memset or strlen for builtins tests with LTO options

[joel at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55994

Joel Sherrill <joel at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |joel at gcc dot gnu.org
         Resolution|                            |FIXED

--- Comment #8 from Joel Sherrill <joel at gcc dot gnu.org> 2013-03-22 16:03:14 UTC ---
Sebastian's patch applied to the head and 4.8 branch. Closing.