[Mesa-dev] [PATCH 2/2] glcpp: Fix so that trailing punctuation does not prevent macro expansion

[Carl Worth]

The trick here is that flex always chooses the rule that matches the most
text. So with a input text of "two:" which we want to be lexed as an
IDENTIFIER token "two" followed by an OTHER token ":" the previous OTHER
rule would match longer as a single token of "two:" which we don't want.

We prevent this by forcing the OTHER pattern to never match a string which
has a first character that could be an identifier (that is _, a-z, or A-Z).
This way the ambiguity is eliminated and this case is lexed correctly.
---
 src/glsl/glcpp/glcpp-lex.l |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/src/glsl/glcpp/glcpp-lex.l b/src/glsl/glcpp/glcpp-lex.l
index 8661887..20d7fc1 100644
--- a/src/glsl/glcpp/glcpp-lex.l
+++ b/src/glsl/glcpp/glcpp-lex.l
@@ -70,7 +70,7 @@ HSPACE		[ \t]
 HASH		^{HSPACE}*#{HSPACE}*
 IDENTIFIER	[_a-zA-Z][_a-zA-Z0-9]*
 PUNCTUATION	[][(){}.&*~!/%<>^|;,=+-]
-OTHER		[^][(){}.&*~!/%<>^|;,=#[:space:]+-]+
+OTHER		[^][_a-zA-Z(){}.&*~!/%<>^|;,=#[:space:]+-][^][(){}.&*~!/%<>^|;,=#[:space:]+-]*
 
 DIGITS			[0-9][0-9]*
 DECIMAL_INTEGER		[1-9][0-9]*[uU]?
-- 
1.7.8.3