[Bug rtl-optimization/28282] New: Attempt to delete prologue/epilogue insn, again

[Bug rtl-optimization/28282] New: Attempt to delete prologue/epilogue insn, again

[ted at midg3t dot net]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
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In a bit of code with an out-of-bounds array access, the following ICN is
triggered:

$ gcc -c -O1 bug.c
bug.c: In function ‘func’:
bug.c:12: error: Attempt to delete prologue/epilogue insn:
(insn/f 64 63 65 0 (set (mem:SI (plus:SI (reg/f:SI 6 bp)
                (const_int -8 [0xfffffffffffffff8])) [0 S4 A8])
        (reg:SI 3 bx)) -1 (nil)
    (nil))
bug.c:12: internal compiler error: in propagate_one_insn, at flow.c:1699
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.
For Debian GNU/Linux specific bug reporting instructions,
see <URL:file:///usr/share/doc/gcc-4.1/README.Bugs>.
Preprocessed source stored into /tmp/ccEvY67W.out file, please attach this to
your bugreport.

This appears to be different from bug 26945 as the test case attached to it
does not trigger any error on my machine.

The test case is as follows:

int global;
int func(int argc) {
        int* array[1];
        array[1] = &global; /* out of bounds, of course */

        if (something(array, argc))
                otherfunc(array);

        if (argc != 17)
                return 17;
}

$ /usr/bin/gcc -v
Using built-in specs.
Target: i486-linux-gnu
Configured with: ../src/configure -v
--enable-languages=c,c++,java,fortran,objc,obj-c++,ada,treelang --prefix=/usr
--enable-shared --with-system-zlib --libexecdir=/usr/lib
--without-included-gettext --enable-threads=posix --enable-nls
--program-suffix=-4.1 --enable-__cxa_atexit --enable-clocale=gnu
--enable-libstdcxx-debug --enable-java-awt=gtk --enable-gtk-cairo
--with-java-home=/usr/lib/jvm/java-1.4.2-gcj-4.1-1.4.2.0/jre --enable-mpfr
--with-tune=i686 --enable-checking=release i486-linux-gnu
Thread model: posix
gcc version 4.1.2 20060630 (prerelease) (Debian 4.1.1-6)


-- 
           Summary: Attempt to delete prologue/epilogue insn, again
           Product: gcc
           Version: 4.1.2
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: rtl-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: ted at midg3t dot net
 GCC build triplet: gcc version 4.1.2 20060630 (prerelease) (Debian 4.1.1-6)
GCC target triplet: i486-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28282

[Bug rtl-optimization/28282] Attempt to delete prologue/epilogue insn, again

[ted at midg3t dot net]

------- Comment #2 from ted at midg3t dot net  2006-07-06 09:29 -------
Created an attachment (id=11841)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=11841&action=view)
Preprocessed source


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28282

[Bug rtl-optimization/28282] Attempt to delete prologue/epilogue insn, again

[ted at midg3t dot net]

------- Comment #1 from ted at midg3t dot net  2006-07-06 09:29 -------
Created an attachment (id=11840)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=11840&action=view)
Test case


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28282

[Bug rtl-optimization/28282] Attempt to delete prologue/epilogue insn, again

[ted at midg3t dot net]

------- Comment #3 from ted at midg3t dot net  2006-07-06 09:35 -------
For clarity, when not run via ccache the first line of the preprocessed source
output is:

// /usr/lib/gcc/i486-linux-gnu/4.1.2/cc1 -quiet bug.c -quiet -dumpbase bug.c
-mtune=i686 -auxbase bug -O1 -o - -frandom-seed=0


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28282

[Bug target/28282] Attempt to delete prologue/epilogue insn, again

[rguenth at gcc dot gnu dot org]

------- Comment #4 from rguenth at gcc dot gnu dot org  2006-07-07 09:44 -------
Confirmed.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rguenth at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
           Keywords|                            |ice-on-valid-code
   Last reconfirmed|0000-00-00 00:00:00         |2006-07-07 09:44:57
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28282

[Bug target/28282] Attempt to delete prologue/epilogue insn, again

[rguenth at gcc dot gnu dot org]

------- Comment #5 from rguenth at gcc dot gnu dot org  2006-07-07 09:45 -------
*** Bug 26945 has been marked as a duplicate of this bug. ***


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |tausq at debian dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28282

[Bug target/28282] Attempt to delete prologue/epilogue insn, again

[rguenth at gcc dot gnu dot org]

------- Comment #6 from rguenth at gcc dot gnu dot org  2006-07-07 09:52 -------
The question is why we need to ICE here.  We may as well go ahead and pretend
it was the users fault and not a bug in some previous pass...


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  BugsThisDependsOn|                            |12535


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28282

[Bug target/28282] Attempt to delete prologue/epilogue insn, again

[pinskia at gcc dot gnu dot org]

------- Comment #7 from pinskia at gcc dot gnu dot org  2006-07-08 04:48 -------
(In reply to comment #6)
The problem is that flow (which does the instruction deletion) is semi stupid
and does not check.  I bet this will be fixed with the dataflow branch or at
least easier to fix :).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28282

[Bug target/28282] Attempt to delete prologue/epilogue insn, again

[pinskia at gcc dot gnu dot org]

------- Comment #8 from pinskia at gcc dot gnu dot org  2007-07-25 19:01 -------
Fixed on the trunk by the dataflow merge.


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pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.3.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28282