https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98011
--- Comment #2 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Regarding OpenACC: There is something going wrong here (-fopenacc):
../testsuite/gfortran.dg/goacc/sentinel-free-form.f95:13:6:
13 | !$ acc parallel ! { dg-error "Unclassifiable statement" }
| 1
Error: Unclassifiable statement at (1)
I do not understand why it parses '!$'. It should regard it as comment; that's
not OpenMP!
* * *
I wrote (for OpenMP's conditional compilation sentinel):
> In free-form source code: "Initial lines must have a space after the
> sentinel".
I wonder whether checking this will break any real-world code.
Otherwise, the following patch would work.
We could also add a warning similar to the OpenACC warning:
Warning: !$ACC at (1) starts a commented line as it neither is followed by a
space nor is a continuation line
to mitigate the real-world code issue.
--- a/gcc/fortran/scanner.c
+++ b/gcc/fortran/scanner.c
@@ -1866,10 +1866,11 @@ load_line (FILE *input, gfc_char_t **pbuf, int
*pbuflen,
/* For truncation and tab warnings, set seen_comment to false if one has
either an OpenMP or OpenACC directive - or a !GCC$ attribute. If
- OpenMP is enabled, use '!$' as as conditional compilation sentinel
- and OpenMP directive ('!$omp'). */
- if (seen_comment && first_comment && flag_openmp && comment_ix + 1 == i
- && c == '$')
+ OpenMP is enabled, use '!$' as as conditional compilation sentinel.
*/
+ if (seen_comment && first_comment && flag_openmp
+ && ((gfc_current_form != FORM_FREE && comment_ix + 1 == i && c ==
'$')
+ || (gfc_current_form == FORM_FREE && comment_ix + 2 == i
+ && (*pbuf)[comment_ix+1] == '$' && c == ' ')))
first_comment = seen_comment = false;
if (seen_comment && first_comment && comment_ix + 4 == i)
{
@@ -1884,6 +1885,12 @@ load_line (FILE *input, gfc_char_t **pbuf, int *pbuflen,
&& ((*pbuf)[comment_ix+3] == 'c' || (*pbuf)[comment_ix+3] == 'C')
&& (c == 'c' || c == 'C'))
first_comment = seen_comment = false;
+ if (flag_openmp
+ && (*pbuf)[comment_ix+1] == '$'
+ && ((*pbuf)[comment_ix+2] == 'o' || (*pbuf)[comment_ix+2] == 'O')
+ && ((*pbuf)[comment_ix+3] == 'm' || (*pbuf)[comment_ix+3] == 'M')
+ && (c == 'p' || c == 'P'))
+ first_comment = seen_comment = false;
}
/* Vendor extension: "<tab>1" marks a continuation line. */
