https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123012
Bug ID: 123012
Summary: Silent acceptance of unquoted character items in
namelist input
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libfortran
Assignee: unassigned at gcc dot gnu.org
Reporter: anlauf at gcc dot gnu.org
Target Milestone: ---
The following code is silently handled by gfortran (and Intel), but
considered bad by NAG and Nvidia:
program nml_quotes_bug
implicit none
integer :: unit = 10
character(8) :: c1, c2
namelist /tovs_obs_chan/ c1, c2
open (unit ,file="nml-quotes-bug.nml")
write(unit,*) "&tovs_obs_chan"
write(unit,*) " c1 = '1',"
write(unit,*) " c2 = 2 ,"
write(unit,*) "/"
rewind(unit)
read (unit ,nml=tovs_obs_chan)
close(unit ,status="delete")
end program nml_quotes_bug
I get:
! NAG:
! Runtime Error: nml-quotes-bug.f90, line 12: Invalid character '2' in NAMELIST
input
! Program terminated by I/O error on unit 10
(File="nml-quotes-bug.nml",Formatted,Sequential)
! Aborted
! Nvidia:
! FIO-F-231/namelist read/unit=10/error on data conversion.
! File name = 'nml-quotes-bug.nml', formatted, sequential access record =
3
! In source file nml-quotes-bug.f90, at line number 12
This looks consistent with F2023:
13.11.3.3 Namelist input values
7th paragraph:
"When the next effective item is of type character, the input form
consists of a sequence of zero or more rep‐chars whose kind type
parameter is implied by the kind of that effective item, delimited
by apostrophes or quotes. ..."
We should reject or at least warn with a -std= option.
