From: Richard Biener <rguenther@suse.de>
Date: Tue, 30 Nov 2021 14:25:17 +0000 (+0100)
Subject: Add comment to indicate tail recursion
X-Git-Tag: basepoints/gcc-13~2684
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=26493af58a1297d5d9fbb061694416deaee71220;p=thirdparty%2Fgcc.git

Add comment to indicate tail recursion

My previous change removed an unreachable break; there (an
unreachable continue; would have been more to the point).  The
following re-adds a comment explaining that WALK_SUBEXPR_TAIL
does not fall through but tail recurses.

2021-11-30  Richard Biener  <rguenther@suse.de>

gcc/fortran/
	* frontend-passes.c (gfc_expr_walker): Add comment to
	indicate tail recursion.
---

diff --git a/gcc/fortran/frontend-passes.c b/gcc/fortran/frontend-passes.c
index 16ee2afc9c0a..4764c834f4f2 100644
--- a/gcc/fortran/frontend-passes.c
+++ b/gcc/fortran/frontend-passes.c
@@ -5229,6 +5229,7 @@ gfc_expr_walker (gfc_expr **e, walk_expr_fn_t exprfn, void *data)
 	  case EXPR_OP:
 	    WALK_SUBEXPR ((*e)->value.op.op1);
 	    WALK_SUBEXPR_TAIL ((*e)->value.op.op2);
+	    /* No fallthru because of the tail recursion above.  */
 	  case EXPR_FUNCTION:
 	    for (a = (*e)->value.function.actual; a; a = a->next)
 	      WALK_SUBEXPR (a->expr);