Hi! In the -fdec-include thread, Mark raised privately that some compilers (verified on fortran.godbolt.org for ifort only myself) do not pad fixed-form lines to the line length like gfortran does. Usually it makes no difference, but if a string constant is continued, it does (including when it appears in include string). We don't pad only with -ffixed-line-length-{0,none}, but that has other effects, like not ignoring characters in column 73+, which is needed for certain sources, e.g. if an include file is written with fixed as well as free form compatible line continuations. ifort apparently has a -pad-source option which defaults to -nopad-source.
This patch introduces similar option, just with a different default (the one that we default to). What is the behavior of DEC fortran, Sun/Oracle fortran and others? If not padding is common to the DEC fortran derived compilers, perhaps -fdec might imply -fno-pad-source ? Ok for trunk if it passes bootstrap/regtest (so far just checked with make check-gfortran RUNTESTFLAGS='dg.exp=pad_source*' )? 2018-11-22 Jakub Jelinek <ja...@redhat.com> * lang.opt (fpad-source): New option. * scanner.c (load_line): Don't pad fixed form lines if !flag_pad_source. * invoke.texi (-fno-pad-source): Document. * gfortran.dg/pad_source_1.f: New test. * gfortran.dg/pad_source_2.f: New test. * gfortran.dg/pad_source_3.f: New test. * gfortran.dg/pad_source_4.f: New test. * gfortran.dg/pad_source_5.f: New test. --- gcc/fortran/lang.opt.jj 2018-11-21 09:06:39.937688966 +0100 +++ gcc/fortran/lang.opt 2018-11-22 09:23:43.090852471 +0100 @@ -536,6 +536,10 @@ ffixed-line-length- Fortran RejectNegative Joined UInteger Var(flag_fixed_line_length) Init(72) -ffixed-line-length-<n> Use n as character line width in fixed mode. +fpad-source +Fortran Var(flag_pad_source) Init(1) +Pad shorter fixed form lines to line width with spaces. + ffpe-trap= Fortran RejectNegative JoinedOrMissing -ffpe-trap=[...] Stop on following floating point exceptions. --- gcc/fortran/scanner.c.jj 2018-11-21 09:06:39.946688820 +0100 +++ gcc/fortran/scanner.c 2018-11-22 09:33:51.861790813 +0100 @@ -1924,6 +1924,7 @@ next_char: /* Pad lines to the selected line length in fixed form. */ if (gfc_current_form == FORM_FIXED && flag_fixed_line_length != 0 + && flag_pad_source && !preprocessor_flag && c != EOF) { --- gcc/fortran/invoke.texi.jj 2018-11-21 21:06:01.869189443 +0100 +++ gcc/fortran/invoke.texi 2018-11-22 10:07:55.285011379 +0100 @@ -121,7 +121,7 @@ by type. Explanations are in the follow -fdec -fdec-structure -fdec-intrinsic-ints -fdec-static -fdec-math @gol -fdec-include -fdefault-double-8 -fdefault-integer-8 -fdefault-real-8 @gol -fdefault-real-10 -fdefault-real-16 -fdollar-ok -ffixed-line-length-@var{n} @gol --ffixed-line-length-none -ffree-form -ffree-line-length-@var{n} @gol +-ffixed-line-length-none -fpad-source -ffree-form -ffree-line-length-@var{n} @gol -ffree-line-length-none -fimplicit-none -finteger-4-integer-8 @gol -fmax-identifier-length -fmodule-private -ffixed-form -fno-range-check @gol -fopenacc -fopenmp -freal-4-real-10 -freal-4-real-16 -freal-4-real-8 @gol @@ -321,8 +321,9 @@ declared as @code{PUBLIC}. @opindex @code{ffixed-line-length-}@var{n} @cindex file format, fixed Set column after which characters are ignored in typical fixed-form -lines in the source file, and through which spaces are assumed (as -if padded to that length) after the ends of short fixed-form lines. +lines in the source file, and, unless @code{-fno-pad-source}, through which +spaces are assumed (as if padded to that length) after the ends of short +fixed-form lines. Popular values for @var{n} include 72 (the standard and the default), 80 (card image), and 132 (corresponding @@ -333,6 +334,15 @@ to them to fill out the line. @option{-ffixed-line-length-0} means the same thing as @option{-ffixed-line-length-none}. +@item -fno-pad-source +@opindex @code{fpad-source} +By default fixed-form lines have spaces assumed (as if padded to that length) +after the ends of short fixed-form lines. This is not done either if +@option{-ffixed-line-length-0}, @option{-ffixed-line-length-none} or +if @option{-fno-pad-source} option is used. With any of those options +continued character constants never have implicit spaces appended +to them to fill out the line. + @item -ffree-line-length-@var{n} @opindex @code{ffree-line-length-}@var{n} @cindex file format, free --- gcc/testsuite/gfortran.dg/pad_source_1.f.jj 2018-11-22 09:43:45.952971238 +0100 +++ gcc/testsuite/gfortran.dg/pad_source_1.f 2018-11-22 09:48:35.933177267 +0100 @@ -0,0 +1,8 @@ +c { dg-do run } +c { dg-skip-if "non-standard options" { *-*-* } { "-ffixed-line-length*" "-f*pad-source" } } + character(80) a + a = 'abc + +def' + if (a(:61) .ne. 'abc') stop 1 + if (a(62:) .ne. 'def') stop 2 + end --- gcc/testsuite/gfortran.dg/pad_source_2.f.jj 2018-11-22 09:43:53.955838929 +0100 +++ gcc/testsuite/gfortran.dg/pad_source_2.f 2018-11-22 09:48:43.254056244 +0100 @@ -0,0 +1,9 @@ +c { dg-do run } +c { dg-skip-if "non-standard options" { *-*-* } { "-ffixed-line-length*" } } +c { dg-options "-fpad-source" } + character(80) a + a = 'abc + +def' + if (a(:61) .ne. 'abc') stop 1 + if (a(62:) .ne. 'def') stop 2 + end --- gcc/testsuite/gfortran.dg/pad_source_3.f.jj 2018-11-22 09:44:23.941343209 +0100 +++ gcc/testsuite/gfortran.dg/pad_source_3.f 2018-11-22 09:44:48.056944540 +0100 @@ -0,0 +1,8 @@ +c { dg-do run } +c { dg-skip-if "non-standard options" { *-*-* } { "-ffixed-line-length*" } } +c { dg-options "-fno-pad-source" } + character(80) a + a = 'abc + +def' + if (a .ne. 'abcdef') stop 1 + end --- gcc/testsuite/gfortran.dg/pad_source_4.f.jj 2018-11-22 09:45:00.395740544 +0100 +++ gcc/testsuite/gfortran.dg/pad_source_4.f 2018-11-22 09:45:13.298527237 +0100 @@ -0,0 +1,7 @@ +c { dg-do run } +c { dg-options "-ffixed-line-length-none" } + character(80) a + a = 'abc + +def' + if (a .ne. 'abcdef') stop 1 + end --- gcc/testsuite/gfortran.dg/pad_source_5.f.jj 2018-11-22 09:45:20.788403413 +0100 +++ gcc/testsuite/gfortran.dg/pad_source_5.f 2018-11-22 09:45:26.860303031 +0100 @@ -0,0 +1,7 @@ +c { dg-do run } +c { dg-options "-ffixed-line-length-0" } + character(80) a + a = 'abc + +def' + if (a .ne. 'abcdef') stop 1 + end Jakub