[Bug middle-end/47401] New: Support for must-not-throw regions with SJLJ exceptions broken

[Bug middle-end/47401] New: Support for must-not-throw regions with SJLJ exceptions broken

[uweigand at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47401

           Summary: Support for must-not-throw regions with SJLJ
                    exceptions broken
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: uweigand@gcc.gnu.org
            Target: spu-elf


A couple of exception related tests are failing on SPU:
FAIL: g++.dg/cpp0x/noexcept04.C execution test
FAIL: g++.dg/cpp0x/noexcept05.C scan-assembler LSDA
FAIL: g++.dg/eh/spec10.C execution test
FAIL: g++.dg/eh/spec11.C scan-assembler LSDA

These are related to must-not-throw regions.  To implement those,
we may have to register a personality function with empty LSDA.
This has been implemented for DWARF CFI exception handling, but
apparently not (fully?) for SJLJ exception handling.

For example, the test case for noexcept05.C:
struct A { ~A(); };
void g();
void f() noexcept
{
  A var;
  g();
}

compiles on the SPU to:
        .global _Z1fv
        .type   _Z1fv, @function
_Z1fv:
        stqd    $lr,16($sp)
        stqd    $sp,-48($sp)
        ai      $sp,$sp,-48
        brsl    $lr,_Z1gv
        ai      $2,$sp,32
        ori     $3,$2,0
        brsl    $lr,_ZN1AD1Ev
        ai      $sp,$sp,48
        lqd     $lr,16($sp)
        bi      $lr
        .size   _Z1fv, .-_Z1fv

Note the absence of any call to _Unwind_SJLJ_Register.

[Bug middle-end/47401] Support for must-not-throw regions with SJLJ exceptions broken

[uweigand at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47401

--- Comment #1 from Ulrich Weigand <uweigand at gcc dot gnu.org> 2011-01-21 16:33:43 UTC ---
Created attachment 23064
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23064
Proposed fix

Patch from http://gcc.gnu.org/ml/gcc-patches/2011-01/msg01406.html

[Bug middle-end/47401] Support for must-not-throw regions with SJLJ exceptions broken

[uweigand at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47401

Ulrich Weigand <uweigand at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #23064|0                           |1
        is obsolete|                            |

--- Comment #2 from Ulrich Weigand <uweigand at gcc dot gnu.org> 2011-01-21 17:18:59 UTC ---
Created attachment 23066
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23066
Updated fix

Updated patch from http://gcc.gnu.org/ml/gcc-patches/2011-01/msg01483.html

[Bug middle-end/47401] Support for must-not-throw regions with SJLJ exceptions broken

[uweigand at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47401

Ulrich Weigand <uweigand at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #23066|0                           |1
        is obsolete|                            |

--- Comment #3 from Ulrich Weigand <uweigand at gcc dot gnu.org> 2011-01-21 17:29:40 UTC ---
Created attachment 23067
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23067
Updated fix

Minor update as requested

[Bug middle-end/47401] Support for must-not-throw regions with SJLJ exceptions broken

[howarth at nitro dot med.uc.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47401

Jack Howarth <howarth at nitro dot med.uc.edu> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |howarth at nitro dot
                   |                            |med.uc.edu

--- Comment #4 from Jack Howarth <howarth at nitro dot med.uc.edu> 2011-01-22 02:49:05 UTC ---
Updated fix regression tested on i386-apple-darwin10 with
-enable-build-with-cxx to stress the use of exception handling...

http://gcc.gnu.org/ml/gcc-testresults/2011-01/msg01914.html

No regressions introduced on darwin.

[Bug middle-end/47401] Support for must-not-throw regions with SJLJ exceptions broken

[uweigand at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47401

--- Comment #5 from Ulrich Weigand <uweigand at gcc dot gnu.org> 2011-01-22 21:24:57 UTC ---
Author: uweigand
Date: Sat Jan 22 21:24:54 2011
New Revision: 169134

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=169134
Log:
    PR middle-end/47401
    * except.c (sjlj_assign_call_site_values): Move setting the
    crtl->uses_eh_lsda flag to ...
    (sjlj_mark_call_sites): ... here.
    (sjlj_emit_function_enter): Support NULL dispatch label.
    (sjlj_build_landing_pads): In a function with no landing pads
    that still has must-not-throw regions, generate code to register
    a personality function with empty LSDA.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/except.c

[Bug middle-end/47401] Support for must-not-throw regions with SJLJ exceptions broken

[uweigand at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47401

Ulrich Weigand <uweigand at gcc dot gnu.org> changed:

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

--- Comment #6 from Ulrich Weigand <uweigand at gcc dot gnu.org> 2011-01-22 21:26:37 UTC ---
Fixed.