https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127823
Bug ID: 127823
Summary: valgrind error in traverse_io_block(gfc_code*, bool*,
gfc_code*) (fron tend-passes.cc:1239)
Product: gcc
Version: 17.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: dcb314 at hotmail dot com
Target Milestone: ---
For this code from the Fujitsu Fortran test suite on github.com:
PROGRAM MAIN
COMPLEX::OBJW(5)
REAL::R1(5),R2(5)
INTEGER::G,F,Y,S,K,J,I,R
OBJW=(3.44,8.44)
OPEN (UNIT=71, FILE='fort.79', FORM='UNFORMATTED')
WRITE(UNIT=71)
((((((((OBJW(I)%RE,I=1,2),J=1,2),K=1,2),S=1,2),R=1,2),Y=1,2),F=1,
2),G=1,2)
WRITE(UNIT=71)
((((((((OBJW(I)%IM,I=1,2),J=1,2),K=1,2),S=1,2),R=1,2),Y=1,2),F=1,
2),G=1,2)
CLOSE (UNIT=71)
OPEN (UNIT=77, FILE='fort.79', FORM='UNFORMATTED')
READ(UNIT=77)
((((((((R1(I),I=1,2),J=1,2),K=1,2),S=1,2),R=1,2),Y=1,2),F=1,2),G=1
,2)
READ(UNIT=77)
((((((((R2(I),I=1,2),J=1,2),K=1,2),S=1,2),R=1,2),Y=1,2),F=1,2),G=1
,2)
CLOSE (UNIT=77,status='delete')
IF( R1(2) .ne. 3.44)print*,'101'
IF( R2(2) .ne. 8.44)print*,'102'
PRINT*,'PASS'
END PROGRAM
the attached code does this:
$ ~/gcc/results.20261009.valgrind/bin/gfortran -c -w -O1 bug1244.f90
==2354827== Invalid read of size 8
==2354827== at 0x695AF6: traverse_io_block(gfc_code*, bool*, gfc_code*)
(frontend-passes.cc:1239)
==2354827== by 0x695ADE: traverse_io_block(gfc_code*, bool*, gfc_code*)
(frontend-passes.cc:1237)
==2354827== by 0x695ADE: traverse_io_block(gfc_code*, bool*, gfc_code*)
(frontend-passes.cc:1237)
==2354827== by 0x695ADE: traverse_io_block(gfc_code*, bool*, gfc_code*)
(frontend-passes.cc:1237)
==2354827== by 0x695ADE: traverse_io_block(gfc_code*, bool*, gfc_code*)
(frontend-passes.cc:1237)
==2354827== by 0x696370: simplify_io_impl_do(gfc_code**, int*, void*)
(frontend-passes.cc:1454)
It was originally file Fortran/0093/0093_0059.f90.
The line of compiler source code is
if (curr != stack_top->code && !*has_reached)
