From: Carl Worth <cworth@cworth.org>
Date: Wed, 25 Jun 2014 18:52:02 +0000 (-0700)
Subject: glsl/glcpp: Don't use start-condition stack when switching to/from <DEFINE>
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=0d5f5d127b2ccac29b12bc7377ccd8cd5b29c70b;p=mesa.git

glsl/glcpp: Don't use start-condition stack when switching to/from <DEFINE>

This commit does not cause any behavioral change for any valid program. Prior
to entering the <DEFINE> start condition, the only valid start condition is
<INITIAL>, so whether pushing/popping <DEFINE> onto the stack or explicit
returning to <INITIAL> is equivalent.

The reason for this change is that we are planning to soon add a start
condition for <HASH> with the following semantics:

	<HASH>: We just saw a directive-introducing '#'

	<DEFINE>: We just saw "#define" starting a directive

With these two start conditions in place, the only correct behavior is to
leave <DEFINE> by returning to <INITIAL>. But the old push/pop code would have
returned to the <HASH> start condition which would then cause an error when
the next directive-introducing '#' would be encountered.

Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
---

diff --git a/src/glsl/glcpp/glcpp-lex.l b/src/glsl/glcpp/glcpp-lex.l
index 798ff4c1a7b..f13b3dacb16 100644
--- a/src/glsl/glcpp/glcpp-lex.l
+++ b/src/glsl/glcpp/glcpp-lex.l
@@ -299,21 +299,21 @@ HEXADECIMAL_INTEGER	0[xX][0-9a-fA-F]+[uU]?
 	 */
 {HASH}define{HSPACE}+ {
 	if (! parser->skipping) {
+		BEGIN DEFINE;
 		yyextra->space_tokens = 0;
-		yy_push_state(DEFINE, yyscanner);
 		RETURN_TOKEN (HASH_DEFINE);
 	}
 }
 
 	/* An identifier immediately followed by '(' */
 <DEFINE>{IDENTIFIER}/"(" {
-	yy_pop_state(yyscanner);
+	BEGIN INITIAL;
 	RETURN_STRING_TOKEN (FUNC_IDENTIFIER);
 }
 
 	/* An identifier not immediately followed by '(' */
 <DEFINE>{IDENTIFIER} {
-	yy_pop_state(yyscanner);
+	BEGIN INITIAL;
 	RETURN_STRING_TOKEN (OBJ_IDENTIFIER);
 }