[Bug c++/17703] [4.0 regression] spurious error about end of function reached

[Bug c++/17703] [4.0 regression] spurious error about end of function reached

[bangerth at dealii dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |4.0.0
      Known to work|                            |3.4.1
   Target Milestone|---                         |4.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug c++/17703] New: [4.0 regression] spurious error about end of function reached

[bangerth at dealii dot org]

Since recently, I get a warning from this piece of code: 
-------------------- 
int foo(int first) { 
  while (true) { 
    return first; 
  } 
} 
-------------------- 
g/x> /home/bangerth/bin/gcc-4.0-pre/bin/c++ -Wall -c x.cc 
x.cc: In function `int foo(int)': 
x.cc:5: warning: control reaches end of non-void function 
 
The message is clearly bogus, since the loop has a return 
statement, but no edge to the end of the while loop. The message 
breaks my nightly -Werror builds since the code is inside libstdc++ 
where I can't fix it (the original code was in std::__unguarded_partition). 
 
This is a regression on mainline that I'd kindly like to ask to have fixed 
soonish... 
 
W.

-- 
           Summary: [4.0 regression] spurious error about end of function
                    reached
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Keywords: diagnostic
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bangerth at dealii dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-09-27 20:33 -------
Confirmed, I should note that cc1 does not have the problem, this is related to while (1) not being 
gimplified to "if(1) else" instead we are making a temparary variable for the 1 and then progating it 
back for optimizations.  This can be considered both a compile-time-hog and memory-hog also.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
          Component|c++                         |middle-end
     Ever Confirmed|                            |1
           Keywords|                            |compile-time-hog, memory-hog
   Last reconfirmed|0000-00-00 00:00:00         |2004-09-27 20:33:33
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[bangerth at ices dot utexas dot edu]

------- Additional Comments From bangerth at ices dot utexas dot edu  2004-09-27 20:42 -------
Subject: Re:  [4.0 regression] spurious error about end of function reached


> This can be considered both a compile-time-hog and memory-hog also.

This would probably give me the honor of having created the shortest testcase 
in these classes :-)

Nevertheless, my request is not just to fix a nuisance in terms of compile 
time or memory consumption, but a definitely wrong warning that makes it 
impossible to compile with -Werrot...

W.

-------------------------------------------------------------------------
Wolfgang Bangerth              email:            bangerth@ices.utexas.edu
                               www: http://www.ices.utexas.edu/~bangerth/



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[reichelt at gcc dot gnu dot org]

------- Additional Comments From reichelt at gcc dot gnu dot org  2004-10-05 14:30 -------
Seconded.

I just tripped over this, too.

Btw, we could add "rejects-valid" to the keywords as well
as it prevents compiles of valid code with "-Werror".


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |reichelt at gcc dot gnu dot
                   |                            |org
           Keywords|                            |monitored


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[bangerth at dealii dot org]

------- Additional Comments From bangerth at dealii dot org  2004-10-05 14:37 -------
Indeed. Let's just do that :-) 

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |critical
           Keywords|                            |rejects-valid


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[reichelt at gcc dot gnu dot org]

------- Additional Comments From reichelt at gcc dot gnu dot org  2004-10-05 18:58 -------
Here's an example using the STL:

=================================
#include <algorithm>

void foo()
{
    int i;
    std::sort(&i,&i+1);
}
=================================


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-06 05:07 -------
I think the problem here is that we are no longer folding CLEANUP_POINT_EXPR < INTEGER_CST <1>> 
into just INTEGER_CST <1>, there is another bug like this.  I will be working on a patch to fix this soon. 
RTH removed the foldding because it was causing too many problems as it removed 
CLEANUP_POINT_EXPR too much.  I will be hugely more conservative when removing 
CLEANUP_POINT_EXPR and I create a function called build_fold_cleanup_point_expr.  This should also 
speed up the compiler in two ways, we never create the CLEANUP_POINT_EXPR in the first place and we 
don't create as many temporaries as before.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-06 13:25 -------
Patch here: <http://gcc.gnu.org/ml/gcc-patches/2004-10/msg00491.html>.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |pinskia at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
           Keywords|                            |patch


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-07 14:55 -------
Newest patch here: <http://gcc.gnu.org/ml/gcc-patches/2004-10/msg00633.html>.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-09 18:22 -------
Newest patch here: <http://gcc.gnu.org/ml/gcc-patches/2004-10/msg00832.html>.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[pinskia at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-10-11 03:42 -------
Subject: Bug 17703

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	pinskia@gcc.gnu.org	2004-10-11 03:42:09

Modified files:
	gcc            : ChangeLog fold-const.c tree.h 
	gcc/cp         : ChangeLog semantics.c typeck.c 
	gcc/testsuite  : ChangeLog 
Added files:
	gcc/testsuite/g++.dg/init: for3.C 
	gcc/testsuite/g++.dg/opt: switch2.C 
	gcc/testsuite/g++.dg/warn: Wreturn-2.C 

Log message:
	2004-10-10  Andrew Pinski  <pinskia@physics.uc.edu>
	
	PR c++/17554
	part of c++/17657
	middle-end/17703
	* semantics.c (maybe_cleanup_point_expr): Call
	fold_build_cleanup_point_expr.
	(maybe_cleanup_point_expr_void): New function.
	(add_decl_expr): Call maybe_cleanup_point_expr_void.
	(finish_expr_stmt): Likewise.
	(finish_return_stmt): Likewise.
	(finish_for_expr): Likewise.
	(finish_asm_stmt): Likewise.
	* typeck.c (condition_conversion): Call
	fold_build_cleanup_point_expr.
	
	2004-10-10  Andrew Pinski  <pinskia@physics.uc.edu>
	
	PR middle-end/17703
	part of PR c++/17657
	* fold-const.c (fold_build_cleanup_point_expr): New function.
	* tree.h (fold_build_cleanup_point_expr): Prototype.
	
	2004-10-10  Andrew Pinski  <pinskia@physics.uc.edu>
	
	PR c++/17554
	* g++.dg/init/for3.C: New test.
	
	PR c++/17657
	* g++.dg/opt/switch2.C: New test.
	
	PR middle-end/17703
	* g++.dg/warn/Wreturn-2.C: New test.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.5829&r2=2.5830
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/fold-const.c.diff?cvsroot=gcc&r1=1.467&r2=1.468
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree.h.diff?cvsroot=gcc&r1=1.636&r2=1.637
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/ChangeLog.diff?cvsroot=gcc&r1=1.4420&r2=1.4421
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/semantics.c.diff?cvsroot=gcc&r1=1.444&r2=1.445
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/typeck.c.diff?cvsroot=gcc&r1=1.581&r2=1.582
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&r1=1.4432&r2=1.4433
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/init/for3.C.diff?cvsroot=gcc&r1=NONE&r2=1.1
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/opt/switch2.C.diff?cvsroot=gcc&r1=NONE&r2=1.1
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/warn/Wreturn-2.C.diff?cvsroot=gcc&r1=NONE&r2=1.1


------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-11 03:42 -------
Fixed.

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703

[Bug middle-end/17703] [4.0 regression] spurious error about end of function reached

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-10-11 03:42 -------
Subject: Bug 17703

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	pinskia@gcc.gnu.org	2004-10-11 03:42:09

Modified files:
	gcc            : ChangeLog fold-const.c tree.h 
	gcc/cp         : ChangeLog semantics.c typeck.c 
	gcc/testsuite  : ChangeLog 
Added files:
	gcc/testsuite/g++.dg/init: for3.C 
	gcc/testsuite/g++.dg/opt: switch2.C 
	gcc/testsuite/g++.dg/warn: Wreturn-2.C 

Log message:
	2004-10-10  Andrew Pinski  <pinskia@physics.uc.edu>
	
	PR c++/17554
	part of c++/17657
	middle-end/17703
	* semantics.c (maybe_cleanup_point_expr): Call
	fold_build_cleanup_point_expr.
	(maybe_cleanup_point_expr_void): New function.
	(add_decl_expr): Call maybe_cleanup_point_expr_void.
	(finish_expr_stmt): Likewise.
	(finish_return_stmt): Likewise.
	(finish_for_expr): Likewise.
	(finish_asm_stmt): Likewise.
	* typeck.c (condition_conversion): Call
	fold_build_cleanup_point_expr.
	
	2004-10-10  Andrew Pinski  <pinskia@physics.uc.edu>
	
	PR middle-end/17703
	part of PR c++/17657
	* fold-const.c (fold_build_cleanup_point_expr): New function.
	* tree.h (fold_build_cleanup_point_expr): Prototype.
	
	2004-10-10  Andrew Pinski  <pinskia@physics.uc.edu>
	
	PR c++/17554
	* g++.dg/init/for3.C: New test.
	
	PR c++/17657
	* g++.dg/opt/switch2.C: New test.
	
	PR middle-end/17703
	* g++.dg/warn/Wreturn-2.C: New test.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.5829&r2=2.5830
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/fold-const.c.diff?cvsroot=gcc&r1=1.467&r2=1.468
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree.h.diff?cvsroot=gcc&r1=1.636&r2=1.637
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/ChangeLog.diff?cvsroot=gcc&r1=1.4420&r2=1.4421
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/semantics.c.diff?cvsroot=gcc&r1=1.444&r2=1.445
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/typeck.c.diff?cvsroot=gcc&r1=1.581&r2=1.582
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&r1=1.4432&r2=1.4433
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/init/for3.C.diff?cvsroot=gcc&r1=NONE&r2=1.1
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/opt/switch2.C.diff?cvsroot=gcc&r1=NONE&r2=1.1
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/warn/Wreturn-2.C.diff?cvsroot=gcc&r1=NONE&r2=1.1



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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17703