[PATCH] Fix LEXLIB and YYTEXT_POINTER on non-ANSI systems.

[Peter Rosin]

Hi!

Below is a patch that makes the lex library detection and
the yytext-pointer tests not stumble when the system does
not provide a unistd.h include.

Ok to push?

Cheers,
Peter

--------------------8<---------------------

* lib/autoconf/programs.m4 (_AC_PROG_LEX_YYTEXT_DECL):
Don't require unistd.h to be present, which it isn't
with, e.g., MSVC.
---
 ChangeLog                |    7 +++++++
 lib/autoconf/programs.m4 |    4 ++++
 2 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 0f67f89..732e388 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2011-12-21  Peter Rosin  <address@hidden>
+
+       Fix LEXLIB and YYTEXT_POINTER on non-ANSI systems.
+       * lib/autoconf/programs.m4 (_AC_PROG_LEX_YYTEXT_DECL):
+       Don't require unistd.h to be present, which it isn't
+       with, e.g., MSVC.
+
 2011-12-07  Paul Eggert  <address@hidden>
 
        AC_LANG_BOOL_COMPILE_TRY(C): port to g++ with warnings
diff --git a/lib/autoconf/programs.m4 b/lib/autoconf/programs.m4
index fb3d8b9..0e97070 100644
--- a/lib/autoconf/programs.m4
+++ b/lib/autoconf/programs.m4
@@ -719,6 +719,10 @@ fi])
 # declares yytext as a char * by default.
 m4_define([_AC_PROG_LEX_YYTEXT_DECL],
 [cat >conftest.l <<_ACEOF[
+%{
+/* avoid non-ANSI #include of unistd.h */
+#define YY_NO_UNISTD_H 1
+%}
 %%
 a { ECHO; }
 b { REJECT; }
-- 
1.7.5.1