[Patch] Fortran's gfc_match_char: %S to match symbol with host_assoc

[Patch] Fortran's gfc_match_char: %S to match symbol with host_assoc

[Tobias Burnus]

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When just matching a symbol, one can use 'gfc_match_symbol (&sym, host_assoc)'
and has the option to match with and without host association.

However, when matching something more complex via 'gfc_match' like
"something ( %s ) , " the match uses host_assoc = false.
While it can be combined ("something (" + symbol + " ) ,"), this requires
keeping track of the previous location and resetting it.

It seems to be much simply to add a new flag supporting host_assoc = true,
which this patch does (using '%S'). The advantage is also that when looking
at the comment or at the "%s" implementation, it is clear that there are two
variants, making it less likely to choose the wrong matching.

OK for mainline?

Tobias

PS: I will use it in an upcoming OpenMP to parse 'uses_allocators'.
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Fortran's gfc_match_char: %S to match symbol with host_assoc

gfc_match ("... %s ...", ...) matches a gfc_symbol but with
host_assoc = 0. This commit adds '%S' as variant which matches
with host_assoc = 1

gcc/fortran/ChangeLog:

	* match.cc (gfc_match_char): Match with '%S' a symbol
	with host_assoc = 1.

diff --git a/gcc/fortran/match.cc b/gcc/fortran/match.cc
index e7be7fddc64..a350ebf754e 100644
--- a/gcc/fortran/match.cc
+++ b/gcc/fortran/match.cc
@@ -1084,7 +1084,8 @@ gfc_match_char (char c, bool gobble_ws)
 
    %%  Literal percent sign
    %e  Expression, pointer to a pointer is set
-   %s  Symbol, pointer to the symbol is set
+   %s  Symbol, pointer to the symbol is set (host_assoc = 0)
+   %S  Symbol, pointer to the symbol is set (host_assoc = 1)
    %n  Name, character buffer is set to name
    %t  Matches end of statement.
    %o  Matches an intrinsic operator, returned as an INTRINSIC enum.
@@ -1151,8 +1152,9 @@ loop:
 	  goto loop;
 
 	case 's':
+	case 'S':
 	  vp = va_arg (argp, void **);
-	  n = gfc_match_symbol ((gfc_symbol **) vp, 0);
+	  n = gfc_match_symbol ((gfc_symbol **) vp, c == 'S');
 	  if (n != MATCH_YES)
 	    {
 	      m = n;

Re: [Patch] Fortran's gfc_match_char: %S to match symbol with host_assoc

[Paul Richard Thomas]

Hi Tobias,

This looks good to me. I'm interested to see it in use :-)

OK for trunk

Paul

On Tue, 20 Jun 2023 at 11:50, Tobias Burnus <tobias@codesourcery.com> wrote:
>
> When just matching a symbol, one can use 'gfc_match_symbol (&sym, host_assoc)'
> and has the option to match with and without host association.
>
> However, when matching something more complex via 'gfc_match' like
> "something ( %s ) , " the match uses host_assoc = false.
> While it can be combined ("something (" + symbol + " ) ,"), this requires
> keeping track of the previous location and resetting it.
>
> It seems to be much simply to add a new flag supporting host_assoc = true,
> which this patch does (using '%S'). The advantage is also that when looking
> at the comment or at the "%s" implementation, it is clear that there are two
> variants, making it less likely to choose the wrong matching.
>
> OK for mainline?
>
> Tobias
>
> PS: I will use it in an upcoming OpenMP to parse 'uses_allocators'.
> -----------------
> Siemens Electronic Design Automation GmbH; Anschrift: Arnulfstraße 201, 80634 München; Gesellschaft mit beschränkter Haftung; Geschäftsführer: Thomas Heurung, Frank Thürauf; Sitz der Gesellschaft: München; Registergericht München, HRB 106955



-- 
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