[Bug middle-end/54664] New: expand_gimple_cond warning for predictably small BRANCH_COST

[Bug middle-end/54664] New: expand_gimple_cond warning for predictably small BRANCH_COST

[amylaar at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54664

             Bug #: 54664
           Summary: expand_gimple_cond warning for predictably small
                    BRANCH_COST
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: amylaar@gcc.gnu.org
            Blocks: 44756
            Target: pdp11-aout


g++ -c   -g -O2 -DIN_GCC -DCROSS_DIRECTORY_STRUCTURE  -fno-exceptions -fno-rtti
-W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute
-pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror
-fno-common  -DHAVE_CONFIG_H -I. -I. -I../../../gcc/gcc -I../../../gcc/gcc/.
-I../../../gcc/gcc/../include -I../../../gcc/gcc/../libcpp/include 
-I../../../gcc/gcc/../libdecnumber -I../../../gcc/gcc/../libdecnumber/dpd
-I../libdecnumber    ../../../gcc/gcc/cfgexpand.c -o cfgexpand.o
../../../gcc/gcc/cfgexpand.c: In function ‘basic_block_def*
expand_gimple_cond(basic_block, gimple)’:
../../../gcc/gcc/cfgexpand.c:1810:65: error: comparison is always true due to
limited range of data type [-Werror=type-limits]
    else if (BRANCH_COST (optimize_insn_for_speed_p (), false) < 4)
                                                                 ^
cc1plus: all warnings being treated as errors
make[2]: *** [cfgexpand.o] Error 1

pdp11.h defines BRANCH_COST as a macro that yield either 0 or 1.

cfgexpand.c:expand_gimple_cond compares this to 4.  Because of the warning
options we use for building cfgexpand.o, we cant't build it for pdp11
configured with --emable-werror-always.

[Bug middle-end/54664] expand_gimple_cond warning for predictably small BRANCH_COST

[hp at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54664

Hans-Peter Nilsson <hp at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |hp at gcc dot gnu.org
      Known to fail|                            |4.10.0, 4.9.1

--- Comment #1 from Hans-Peter Nilsson <hp at gcc dot gnu.org> ---
Also seen for 4.9.1 and 4.10.0 i.e. trunk r212879.

[Bug middle-end/54664] expand_gimple_cond -Wtype-limits warning for predictably small BRANCH_COST

[egallager at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54664

Eric Gallager <egallager at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |egallager at gcc dot gnu.org
     Ever confirmed|0                           |1
   Last reconfirmed|2013-02-25 00:00:00         |2021-03-19
             Status|UNCONFIRMED                 |ASSIGNED

--- Comment #4 from Eric Gallager <egallager at gcc dot gnu.org> ---
ASSIGNED since someone put themselves as the assignee.

[Bug middle-end/54664] expand_gimple_cond -Wtype-limits warning for predictably small BRANCH_COST

[paulkoning at comcast dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54664

--- Comment #5 from paulkoning at comcast dot net ---
I didn't realize that's part of the protocol.  Thanks Eric.

        paul

> On Mar 19, 2021, at 6:01 PM, egallager at gcc dot gnu.org <gcc-bugzilla@gcc.gnu.org> wrote:
> 
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54664
> 
> Eric Gallager <egallager at gcc dot gnu.org> changed:
> 
>           What    |Removed                     |Added
> ----------------------------------------------------------------------------
>                 CC|                            |egallager at gcc dot gnu.org
>     Ever confirmed|0                           |1
>   Last reconfirmed|2013-02-25 00:00:00         |2021-03-19
>             Status|UNCONFIRMED                 |ASSIGNED
> 
> --- Comment #4 from Eric Gallager <egallager at gcc dot gnu.org> ---
> ASSIGNED since someone put themselves as the assignee.
> 
> -- 
> You are receiving this mail because:
> You are on the CC list for the bug.
> You are the assignee for the bug.

[Bug middle-end/54664] expand_gimple_cond -Wtype-limits warning for predictably small BRANCH_COST

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54664

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |6.0
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fixed in GCC 6 by r6-3577-gef295bcefe9791 (though BRANCH_COST changed again in
GCC 9 to be defined as 1 in r9-1500-gb4324a144b4499 ).