https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68717
Bug ID: 68717
Summary: [6 Regression] New (bogus?) warnings when compiling
some gfortran.dg tests with -flto after r231239
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: lto
Assignee: unassigned at gcc dot gnu.org
Reporter: dominiq at lps dot ens.fr
CC: hubicka at gcc dot gnu.org
Target Milestone: ---
The following tests fail when compiled with -flto after r231239
FAIL: gfortran.dg/assumed_rank_1.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/assumed_rank_8.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/assumed_rank_9.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/assumed_rank_2.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/cshift_large_1.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/elemental_subroutine_3.f90 -g -flto (test for excess
errors)
FAIL: gfortran.dg/eoshift_large_1.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/func_derived_1.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/matmul_3.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/matmul_6.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/reshape-complex.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/zero_sized_1.f90 -g -flto (test for excess errors)
with both -m32 and -m64, the following two tests are only compiled with -m64
and fail
FAIL: gfortran.dg/cshift_large_1.f90 -g -flto (test for excess errors)
FAIL: gfortran.dg/eoshift_large_1.f90 -g -flto (test for excess errors)
The typical error is
/opt/gcc/_clean/gcc/testsuite/gfortran.dg/matmul_3.f90:22:0: warning: type of
'_gfortran_matmul_i4' does not match original declaration [-Wlto-type-mismatch]
iX2(1:n,1) = matmul( iB(2,1:n),iC(1:n,1:n) )
/opt/gcc/_clean/gcc/testsuite/gfortran.dg/matmul_3.f90:22:0: warning: type of
'_gfortran_matmul_i4' does not match original declaration [-Wlto-type-mismatch]
/opt/gcc/_clean/gcc/testsuite/gfortran.dg/matmul_3.f90:33:0: note:
'_gfortran_matmul_i4' was previously declared here
iX2 = matmul (transpose (iB), iC)
/opt/gcc/_clean/gcc/testsuite/gfortran.dg/matmul_3.f90:33:0: note: code may be
misoptimized unless -fno-strict-aliasing is used
The warnings do not require -fstrict-aliasing and are not suppressed with
-fno-strict-aliasing (as it is the case for pr68649).
These -flto failures are detected by using the following patch
--- ../_clean/gcc/testsuite/lib/gfortran-dg.exp 2015-05-16 15:02:44.000000000
+0200
+++ ../p_work/gcc/testsuite/lib/gfortran-dg.exp 2015-05-16 15:03:53.000000000
+0200
@@ -125,8 +125,18 @@ proc gfortran-dg-runtest { testcases fla
# we cycle through the option list, otherwise we don't
if [expr [search_for $test "dg-do run"]] {
set option_list $torture_with_loops
+ if [check_effective_target_lto] {
+ lappend option_list { -g -flto }
+ # lappend option_list { -g -O3 -fwhole-program -flto }
+ }
} else {
set option_list [list { -O } ]
+ if [check_effective_target_lto] {
+ # lappend option_list { -g -flto }
+ # lappend option_list { -g -O3 -fwhole-program -flto }
+ # lappend option_list { -flto }
+ # lappend option_list { -O3 -fwhole-program -flto }
+ }
}
set nshort [file tail [file dirname $test]]/[file tail $test]
