[Bug c/57287] New: GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[Bug c/57287] New: GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[muhammad_bilal at mentor dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

            Bug ID: 57287
           Summary: GCC 4.9.0 fails to build GDB on Ubuntu 12.04
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: muhammad_bilal at mentor dot com

While I was building the latest GDB CVS source code with
gcc (GCC) 4.9.0 20130513 (experimental)
with building step
with building step 

$CC="/home/mbilal/gcc-svn/install/bin/gcc" ./../src/configure
--prefix=/home/mbilal/commit-gdb-cvs/install

$ make

I got errors

 -MF .deps/py-framefilter.Tpo -fno-strict-aliasing -DNDEBUG -fwrapv
.././../src/gdb/python/py-framefilter.c
In file included from .././../src/gdb/python/py-framefilter.c:24:0:
.././../src/gdb/python/py-framefilter.c: In function ‘enumerate_locals’:
.././../src/gdb/exceptions.h:152:31: error: ‘buf’ may be used uninitialized in
this function [-Werror=maybe-uninitialized]
        EXCEPTIONS_SIGJMP_BUF *buf = \
                               ^
.././../src/gdb/exceptions.h:152:31: note: ‘buf’ was declared here
        EXCEPTIONS_SIGJMP_BUF *buf = \
                               ^
.././../src/gdb/python/py-framefilter.c:839:7: note: in expansion of macro
‘TRY_CATCH’
       TRY_CATCH (except, RETURN_MASK_ALL)
       ^
.././../src/gdb/exceptions.h:152:31: error: ‘buf’ may be used uninitialized in
this function [-Werror=maybe-uninitialized]
        EXCEPTIONS_SIGJMP_BUF *buf = \
                               ^
.././../src/gdb/exceptions.h:152:31: note: ‘buf’ was declared here
        EXCEPTIONS_SIGJMP_BUF *buf = \
                               ^
.././../src/gdb/python/py-framefilter.c:782:7: note: in expansion of macro
‘TRY_CATCH’
       TRY_CATCH (except, RETURN_MASK_ALL)
       ^
.././../src/gdb/exceptions.h:152:31: error: ‘buf’ may be used uninitialized in
this function [-Werror=maybe-uninitialized]
        EXCEPTIONS_SIGJMP_BUF *buf = \
                               ^
.././../src/gdb/exceptions.h:152:31: note: ‘buf’ was declared here
        EXCEPTIONS_SIGJMP_BUF *buf = \
                               ^
.././../src/gdb/python/py-framefilter.c:762:4: note: in expansion of macro
‘TRY_CATCH’
    TRY_CATCH (except, RETURN_MASK_ALL)
    ^
.././../src/gdb/python/py-framefilter.c:732:23: error: ‘locals_cleanups’ may be
used uninitialized in this function [-Werror=maybe-uninitialized]
       struct cleanup *locals_cleanups;
                       ^
.././../src/gdb/python/py-framefilter.c:731:11: error: ‘local_indent’ may be
used uninitialized in this function [-Werror=maybe-uninitialized]
       int local_indent = 8 + (8 * indent);
           ^
cc1: all warnings being treated as errors
make[2]: *** [py-framefilter.o] Error 1
make[2]: Leaving directory `/home/mbilal/commit-gdb-cvs/objdir/gdb'
make[1]: *** [all-gdb] Error 2
make[1]: Leaving directory `/home/mbilal/commit-gdb-cvs/objdir'
make: *** [all] Error 2


But something looks really bogus with errors like

.././../src/gdb/python/py-framefilter.c:731:11: error: ‘local_indent’ may be
used uninitialized in this function [-Werror=maybe-uninitialized]
       int local_indent = 8 + (8 * indent);

First I reported a bug on GDB bugzilla
http://sourceware.org/bugzilla/show_bug.cgi?id=15463#c4
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From: "muhammad_bilal at mentor dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04
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http://gcc.gnu.org/bugzilla/show_bug.cgi?idW287

hmb <muhammad_bilal at mentor dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |blocker

[Bug c/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[palves at redhat dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

Pedro Alves <palves at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |palves at redhat dot com

--- Comment #1 from Pedro Alves <palves at redhat dot com> ---
(Repeating my comment on the GDB bugzilla here)

All these warnings are around setjmp/longjmp.

E.g, with:

.././../src/gdb/python/py-framefilter.c:731:11: error: ‘local_indent’ may be
used uninitialized in this function [-Werror=maybe-uninitialized]
       int local_indent = 8 + (8 * indent);

local_indent is only used in a TRY_CATCH block, meaning, after a setjmp.

I suspect this to be related to this recent setjmp gcc change:

 http://gcc.gnu.org/ml/gcc-patches/2013-05/msg00344.html
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Subject: [Bug middle-end/57286] [4.9 regression] infinite recurison in fold-const.c:10037
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http://gcc.gnu.org/bugzilla/show_bug.cgi?idW286

--- Comment #3 from Marc Glisse <glisse at gcc dot gnu.org> ---
Intuitively, I'd say:

@@ -10041,7 +10041,7 @@

       if (TREE_CODE (arg1) == COND_EXPR
       || TREE_CODE (arg1) == VEC_COND_EXPR
-      || COMPARISON_CLASS_P (arg1))
+      || (COMPARISON_CLASS_P (arg1) && !VECTOR_TYPE_P (TREE_TYPE (arg1))))
     {
       tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
                              arg1, arg0,

but I don't really have time to think about it right now (meeting).

[Bug c/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2013-05-15
     Ever confirmed|0                           |1

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Please attach at least one example as preprocessed source.

[Bug middle-end/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[palves at redhat dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #3 from Pedro Alves <palves at redhat dot com> ---
hmb,

could you do that?

See instructions here: http://gcc.gnu.org/bugs/

[Bug middle-end/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[muhammad_bilal at mentor dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #4 from hmb <muhammad_bilal at mentor dot com> ---
I am attaching the all preprocessed source code of GDB
here is the link https://www.dropbox.com/s/ldml34p3lov867w/gcc-bug.zip

[Bug middle-end/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed with -O2 -Wall.

[Bug middle-end/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
Created attachment 30172
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30172&action=edit
preprocessed source

[Bug middle-end/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
Created attachment 30175
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30175&action=edit
somewhat reduced testcase

Autoreduced on level 0.

[Bug middle-end/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
Created attachment 30176
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30176&action=edit
more reduced

[Bug middle-end/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #10 from Richard Biener <rguenth at gcc dot gnu.org> ---
#include <setjmp.h>
jmp_buf buf;
void foo (int);
void bar (int) __attribute__((leaf));
void enumerate_locals (int indent)
{
  foo (0);
  while (indent--)     
    {
      int local_indent = 8 + (8 * indent);
      if (local_indent != 8)
        {
          setjmp (buf);
          bar (local_indent);
        }
    }
  foo (1);
}


warns about uninitialized local_indent.  The abnormal edges we insert
for foo (0) make undefined values flow into the setjmp block.

[Bug middle-end/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #11 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Fri May 24 12:44:58 2013
New Revision: 199289

URL: http://gcc.gnu.org/viewcvs?rev=199289&root=gcc&view=rev
Log:
2013-05-24  Richard Biener  <rguenther@suse.de>

    PR tree-optimization/57287
    * tree-ssa-uninit.c (compute_uninit_opnds_pos): Disregard
    all SSA names that occur in abnormal PHIs.

    * gcc.dg/pr57287.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/pr57287.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-uninit.c

[Bug middle-end/57287] GCC 4.9.0 fails to build GDB on Ubuntu 12.04

[meadori at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

meadori at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |meadori at gcc dot gnu.org

--- Comment #14 from meadori at gcc dot gnu.org ---
(In reply to hmb from comment #13)
> Created attachment 30201 [details]
> preprocessed source code
> 
> Attaching the preprocessed source code

Here is a reduction (as of trunk today):

$ cat test.c
#include <setjmp.h>
#include <stdio.h>

struct node
{
  struct node *next;
  char *name;
} *list;

struct node *list;
struct node *head (void);

sigjmp_buf *bar (void);

int baz (void)
{
  struct node *n;
  int varseen = 0;

  list = head ();
  for (n = list; n; n = n->next)
    {
      if (!varseen)
          varseen = 1;

      sigjmp_buf *buf = bar ();
      __sigsetjmp (*buf, 1);
    }

  if (!varseen)
    return 0;
  return 1;
}
$ i686-pc-linux-gnu-gcc --version
i686-pc-linux-gnu-gcc (GCC) 4.9.0 20130819 (experimental)
Copyright (C) 2013 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ i686-pc-linux-gnu-gcc -Wall -O2 -c test.c
test.c: In function 'baz':
test.c:26:19: warning: 'buf' may be used uninitialized in this function
[-Wmaybe-uninitialized]
       sigjmp_buf *buf = bar ();
                   ^

[Bug middle-end/57287] [4.9 Regression] Bogous uninitialized warning with abnormal control flow

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |diagnostic
             Status|REOPENED                    |NEW
                 CC|rguenther at suse dot de           |rguenth at gcc dot gnu.org
   Target Milestone|---                         |4.9.0
            Summary|GCC 4.9.0 fails to build    |[4.9 Regression] Bogous
                   |GDB on Ubuntu 12.04         |uninitialized warning with
                   |                            |abnormal control flow

--- Comment #15 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.  David, can you have a look here?  I had a hard time following what
exactly to do with the dataflow in the uninit pass for abnormal control flow
(abnormal control flow should be considered receiving an initialized value).

Thanks.

[Bug middle-end/57287] [4.9 Regression] Bogous uninitialized warning with abnormal control flow

[xinliangli at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #16 from davidxl <xinliangli at gmail dot com> ---
(In reply to Richard Biener from comment #15)
> Confirmed.  David, can you have a look here?  I had a hard time following
> what
> exactly to do with the dataflow in the uninit pass for abnormal control flow
> (abnormal control flow should be considered receiving an initialized value).
> 
> Thanks.


I looked at it a little. The warning is not from the predicated uninit analysis
which checks uses of phi defs.  The warning is emitted from tree-ssa.c:1644 in
function warn_uninitialized_vars. It warns about the 'definitely' uninitialized
variable that may be executed. In this case it is use of 'buf_16(ab)' in BB3. 
Not sure where this statement comes from:

buf_24 = buf_16(ab);

The dot file is attached.

digraph "uninit.c.131t.uninit1" {
overlap=false;
subgraph "baz" {
    color="black";
    label="baz";
    fn_11_basic_block_0
[shape=Mdiamond,style=filled,fillcolor=white,label="ENTRY"];

    fn_11_basic_block_1
[shape=Mdiamond,style=filled,fillcolor=white,label="EXIT"];

    fn_11_basic_block_2 [shape=record,style=filled,fillcolor=lightgrey,label="{
FREQ:10000 |\<bb\ 2\>:\l\
|varseen_11(ab)\ =\ 0;\l\
|_14\ =\ head\ ();\l\
}"];

    fn_11_basic_block_3 [shape=record,style=filled,fillcolor=lightgrey,label="{
FREQ:7100 |\<bb\ 3\>:\l\
|list\ =\ _14;\l\
|buf_24\ =\ buf_16(ab);\l\
|if\ (_14\ !=\ 0B)\l\
\ \ goto\ \<bb\ 4\>;\l\
else\l\
\ \ goto\ \<bb\ 8\>;\l\
}"];

    fn_11_basic_block_4 [shape=record,style=filled,fillcolor=lightgrey,label="{
FREQ:8500 |\<bb\ 4\>:\l\
|#\ varseen_3(ab)\ =\ PHI\ \<1(3),\ 1(6)\>\l\
|#\ n_26(ab)\ =\ PHI\ \<_14(3),\ n_2(ab)(6)\>\l\
|#\ buf_27(ab)\ =\ PHI\ \<buf_24(3),\ buf_7(ab)(6)\>\l\
|buf_21\ =\ bar\ ();\l\
}"];

    fn_11_basic_block_5 [shape=record,style=filled,fillcolor=lightgrey,label="{
FREQ:4250 |\<bb\ 5\>:\l\
}"];

    fn_11_basic_block_6 [shape=record,style=filled,fillcolor=lightgrey,label="{
FREQ:2900 |\<bb\ 6\>:\l\
|#\ n_1(ab)\ =\ PHI\ \<n_15(ab)(2),\ n_26(ab)(4),\ n_26(ab)(5)\>\l\
|#\ varseen_4(ab)\ =\ PHI\ \<varseen_11(ab)(2),\ varseen_3(ab)(4),\
varseen_3(ab)(5)\>\l\
|#\ buf_6(ab)\ =\ PHI\ \<buf_16(ab)(2),\ buf_27(ab)(4),\ buf_21(5)\>\l\
|__sigsetjmp\ (buf_6(ab),\ 1);\l\
|n_19\ =\ n_1(ab)-\>next;\l\
|n_2(ab)\ =\ n_19;\l\
|varseen_5\ =\ varseen_4(ab);\l\
|buf_7(ab)\ =\ buf_6(ab);\l\
|if\ (n_2(ab)\ !=\ 0B)\l\
\ \ goto\ \<bb\ 4\>;\l\
else\l\
\ \ goto\ \<bb\ 7\>;\l\
}"];

    fn_11_basic_block_7 [shape=record,style=filled,fillcolor=lightgrey,label="{
FREQ:1500 |\<bb\ 7\>:\l\
|_25\ =\ varseen_5;\l\
}"];

    fn_11_basic_block_8 [shape=record,style=filled,fillcolor=lightgrey,label="{
FREQ:1500 |\<bb\ 8\>:\l\
|#\ _8\ =\ PHI\ \<_25(7),\ 0(3)\>\l\
|return\ _8;\l\
}"];

    fn_11_basic_block_0:s -> fn_11_basic_block_2:n
[style="solid,bold",color=blue,weight=100,constraint=true, label="[100%]"];
    fn_11_basic_block_2:s -> fn_11_basic_block_6:n
[style="solid,bold",color=red,weight=10,constraint=true, label="[29%]"];
    fn_11_basic_block_2:s -> fn_11_basic_block_3:n
[style="solid,bold",color=blue,weight=100,constraint=true, label="[71%]"];
    fn_11_basic_block_3:s -> fn_11_basic_block_4:n
[style="solid,bold",color=black,weight=10,constraint=true, label="[85%]"];
    fn_11_basic_block_3:s -> fn_11_basic_block_8:n
[style="solid,bold",color=black,weight=10,constraint=true, label="[15%]"];
    fn_11_basic_block_4:s -> fn_11_basic_block_6:n
[style="dotted,bold",color=red,weight=10,constraint=false, label="[50%]"];
    fn_11_basic_block_4:s -> fn_11_basic_block_5:n
[style="solid,bold",color=blue,weight=100,constraint=true, label="[50%]"];
    fn_11_basic_block_5:s -> fn_11_basic_block_6:n
[style="dotted,bold",color=blue,weight=10,constraint=false, label="[100%]"];
    fn_11_basic_block_6:s -> fn_11_basic_block_4:n
[style="solid,bold",color=black,weight=10,constraint=true, label="[85%]"];
    fn_11_basic_block_6:s -> fn_11_basic_block_7:n
[style="solid,bold",color=black,weight=10,constraint=true, label="[15%]"];
    fn_11_basic_block_7:s -> fn_11_basic_block_8:n
[style="solid,bold",color=blue,weight=100,constraint=true, label="[100%]"];
    fn_11_basic_block_8:s -> fn_11_basic_block_1:n
[style="solid,bold",color=black,weight=10,constraint=true, label="[100%]"];
    fn_11_basic_block_0:s -> fn_11_basic_block_1:n
[style="invis",constraint=true];
}
}

[Bug middle-end/57287] [4.9 Regression] Bogus uninitialized warning with abnormal control flow

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #17 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to davidxl from comment #16)
> (In reply to Richard Biener from comment #15)
> > Confirmed.  David, can you have a look here?  I had a hard time following
> > what
> > exactly to do with the dataflow in the uninit pass for abnormal control flow
> > (abnormal control flow should be considered receiving an initialized value).
> > 
> > Thanks.
> 
> 
> I looked at it a little. The warning is not from the predicated uninit
> analysis which checks uses of phi defs.  The warning is emitted from
> tree-ssa.c:1644 in function warn_uninitialized_vars. It warns about the
> 'definitely' uninitialized variable that may be executed. In this case it is
> use of 'buf_16(ab)' in BB3.  Not sure where this statement comes from:
> 
> buf_24 = buf_16(ab);

Oh, sorry for not looking close enough again.  It is jump-threading introducing
this copy by duplicating a block with an abnormal PHI.

Not sure why it chooses to duplicate it - I see no jump threads registered
by DOM at -O1 - probably because:

  if (dump_file && (dump_flags & TDF_DETAILS)
      && e->dest != e2->src)
    fprintf (dump_file,
             "  Registering jump thread around one or more intermediate
blocks\n");

(gdb) p threaded_edges.vec_->vecdata_[0]->dest
$7 = <basic_block 0x7ffff6e1a4e0 (9)>
(gdb) p threaded_edges.vec_->vecdata_[1]->src
$8 = <basic_block 0x7ffff6e1a4e0 (9)>

but thats the jump threading it performs as it can optimize the if (!varseen)
check.

>From looking at the symptoms - warning about buf_16(D)(ab) use in

  buf_24 = buf_16(D)(ab);

it seems simplest to disregard SSA names occuring in abnormal PHIs ...

[Bug middle-end/57287] [4.9 Regression] Bogus uninitialized warning with abnormal control flow

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #18 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Thu Aug 29 11:20:16 2013
New Revision: 202069

URL: http://gcc.gnu.org/viewcvs?rev=202069&root=gcc&view=rev
Log:
2013-08-29  Richard Biener  <rguenther@suse.de>

    PR middle-end/57287
    * tree-ssa-copy.c (may_propagate_copy): Allow propagating
    of default defs that appear in abnormal PHI nodes.

    * gcc.dg/pr57287-2.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/pr57287-2.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-copy.c

[Bug middle-end/57287] [4.9 Regression] Bogus uninitialized warning with abnormal control flow

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #19 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed again.

[Bug middle-end/57287] [4.9 Regression] Bogus uninitialized warning with abnormal control flow

[meadori at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #20 from meadori at gcc dot gnu.org ---
Confirmed fix.

I can also now build GDB trunk with GCC trunk (both from today).

Thanks Richard!

[Bug middle-end/57287] [4.9 Regression] Bogus uninitialized warning with abnormal control flow

[amylaar at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |amylaar at gcc dot gnu.org

--- Comment #21 from Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #18)

> Added:
>     trunk/gcc/testsuite/gcc.dg/pr57287-2.c

Why is that using __sigsetjmp ?  That's not a standard function.
E.g. newlib doesn't have it.

[Bug middle-end/57287] [4.9 Regression] Bogus uninitialized warning with abnormal control flow

[rguenther at suse dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #22 from rguenther at suse dot de <rguenther at suse dot de> ---
On Tue, 3 Sep 2013, amylaar at gcc dot gnu.org wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287
> 
> Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> changed:
> 
>            What    |Removed                     |Added
> ----------------------------------------------------------------------------
>                  CC|                            |amylaar at gcc dot gnu.org
> 
> --- Comment #21 from Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> ---
> (In reply to Richard Biener from comment #18)
> 
> > Added:
> >     trunk/gcc/testsuite/gcc.dg/pr57287-2.c
> 
> Why is that using __sigsetjmp ?  That's not a standard function.
> E.g. newlib doesn't have it.

Sorry, I forgot to change it to setjmp.  Done now.

[Bug middle-end/57287] [4.9 Regression] Bogus uninitialized warning with abnormal control flow

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57287

--- Comment #23 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Tue Sep  3 07:53:05 2013
New Revision: 202197

URL: http://gcc.gnu.org/viewcvs?rev=202197&root=gcc&view=rev
Log:
2013-09-03  Richard Biener  <rguenther@suse.de>

    PR middle-end/57287
    * gcc.dg/pr57287-2.c: Use setjmp, not __sigsetjmp.

Modified:
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/pr57287-2.c