https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70684
Bug ID: 70684
Summary: incorrect reading of values from file on Windows
Product: gcc
Version: 5.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libfortran
Assignee: unassigned at gcc dot gnu.org
Reporter: ajmay81 at googlemail dot com
Target Milestone: ---
When writing and then reading back values from a file on Windows (program built
with gfortran via mxe cross compiler) the wrong values are read. Here is a
trivial example:
program test
implicit none
integer,parameter :: isize=12
integer,parameter :: funit=12
integer :: i
double precision, dimension(isize) :: a
do i=1,isize
a(i)=dble(i)
enddo
write(6,*)'Value to write'
do i=1,isize
write(6,*)a(i)
enddo
open(funit,file='test.txt')
write(funit,'(1x,6(f25.20,'',''))') (a(i),i=1,isize)
close(funit)
do i=1,isize
a(i)=0d0
enddo
open(funit,file='test.txt')
read(funit,*) (a(i),i=1,isize)
close(funit)
write(6,*)'Values after read'
do i=1,isize
write(6,*)a(i)
enddo
end
And compiled with:
x86_64-w64-mingw32.static-gfortran test.f90
On Linux the values 1-12 are read, but on Windows the values 1-6,0,7-11 are
read. It seems that the file is written with Windows line endings on Windows,
but when read Linux line endings are expected. I think it should be consistent,
at least one should be able to read files back on the same system they are
generated.
I grepped through a recent 5.3.0 tarball, and it's a bit of a guess but in
libgfortran/io/transfer.c the function next_record_r() knows only about '\n'
line endings, yet it's opposite number next_record_w() knows about both '\n'
and '\r' - so perhaps the same logic just needs copying to the read function?
