[Bug c++/13764] New: [tree-ssa] g++ creates extra blocks

[Bug c++/13764] New: [tree-ssa] g++ creates extra blocks

[dann at godzilla dot ics dot uci dot edu]

This function: 

void bar (void)
{
  int a;
}

when compiled with g++
is dumped as: 

;; Function void bar() (_Z3barv)
;; enabled by -tree-original

{
   { // extra block, should not be needed
      int a
   } 
}

when compiled with gcc 

;; Function bar (bar)
;; enabled by -tree-original

{
   int a
}


The extra blocks created are also confirmed by -fmem-report:
for gcc:
blocks                     3        132
for g++:
blocks                     5        220

-- 
           Summary: [tree-ssa] g++ creates extra blocks
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: dann at godzilla dot ics dot uci dot edu
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13764

[Bug c++/13764] [tree-ssa] g++ creates extra blocks

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-01-20 15:18 -------
Confirmed.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
           Keywords|                            |memory-hog
   Last reconfirmed|0000-00-00 00:00:00         |2004-01-20 15:18:24
               date|                            |
   Target Milestone|---                         |tree-ssa


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13764

[Bug c++/13764] [tree-ssa] g++ creates extra blocks

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |enhancement


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13764

[Bug c++/13764] [tree-ssa] g++ creates extra blocks

[rth at gcc dot gnu dot org]

------- Additional Comments From rth at gcc dot gnu dot org  2004-01-23 03:15 -------
The block comment in front of begin_function_body reads:

/* Do the necessary processing for the beginning of a function body, which
   in this case includes member-initializers, but not the catch clauses of
   a function-try-block.  Currently, this means opening a binding level
   for the member-initializers (in a ctor) and member cleanups (in a dtor).
   In other functions, this isn't necessary, but it doesn't hurt.  */

This is, incidentally, not specific to tree-ssa.

Jason, you get the bag.  Personally, I don't care if you add what
small check might be needed, or close WONTFIX.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |jason at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13764

[Bug c++/13764] c++ front-end creates extra blocks

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[tree-ssa] g++ creates extra|c++ front-end creates extra
                   |blocks                      |blocks
   Target Milestone|tree-ssa                    |---
            Version|tree-ssa                    |3.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13764

[Bug c++/13764] c++ front-end creates extra blocks

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-01-26 22:28 -------
*** Bug 13871 has been marked as a duplicate of this bug. ***

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13764

[Bug c++/13764] c++ front-end creates extra blocks

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-07-26 18:31 -------
This is also a compile time hog as we have to go through the extra blocks both in GC and when 
converting to gimple and to lower gimple.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |compile-time-hog


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13764

[Bug c++/13764] c++ front-end creates extra blocks

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2005-09-27 16:26 -------
Subject: Bug 13764

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	jason@gcc.gnu.org	2005-09-27 16:04:25

Modified files:
	gcc            : ChangeLog c-common.c 
	gcc/cp         : ChangeLog cp-tree.h name-lookup.c decl.c 
Added files:
	gcc/testsuite/g++.dg/tree-ssa: block1.C 

Log message:
	PR c++/13764
	* c-common.c (finish_fname_decls): Use append_to_statement_list_force.
	* cp/cp-tree.h (FUNCTION_NEEDS_BODY_BLOCK): New macro.
	* cp/name-lookup.c (pushdecl_maybe_friend): Check it.
	* cp/decl.c (begin_function_body): Do nothing if it's false.
	(finish_function_body): Ditto.
	(outer_curly_brace_block): New fn.
	(finish_function): Use it.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.10030&r2=2.10031
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/c-common.c.diff?cvsroot=gcc&r1=1.652&r2=1.653
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/ChangeLog.diff?cvsroot=gcc&r1=1.4902&r2=1.4903
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/cp-tree.h.diff?cvsroot=gcc&r1=1.1164&r2=1.1165
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/name-lookup.c.diff?cvsroot=gcc&r1=1.141&r2=1.142
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/decl.c.diff?cvsroot=gcc&r1=1.1427&r2=1.1428
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/tree-ssa/block1.C.diff?cvsroot=gcc&r1=NONE&r2=1.1



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13764

[Bug c++/13764] c++ front-end creates extra blocks

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-09-27 20:55 -------
Fixed.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.1.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13764