Regenerate lexer source code

Revise the manual procedure in the `*Lexer.in.l` files.  Some of our
post-processing steps are no longer necessary with the current set of
supported compilers.  Some steps changed with newer versions of flex.

Then regenerate all lexers with flex version 2.6.1.

1 files changed, 8 insertions, 16 deletions

diff --git a/Source/cmExprLexer.in.l b/Source/cmExprLexer.in.l
index e32abd9992..25ddba4604 100644
--- a/Source/cmExprLexer.in.l
+++ b/Source/cmExprLexer.in.l
@@ -3,29 +3,21 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 /*
 
-This file must be translated to C and modified to build everywhere.
+This file must be translated to C++ and modified to build everywhere.
 
-Run flex like this:
+Run flex >= 2.6 like this:
 
-  flex --prefix=cmExpr_yy --header-file=cmExprLexer.h -ocmExprLexer.cxx cmExprLexer.in.l
+  flex --nounistd -DFLEXINT_H --prefix=cmExpr_yy --header-file=cmExprLexer.h -ocmExprLexer.cxx cmExprLexer.in.l
 
 Modify cmExprLexer.cxx:
-  - remove TABs
-  - remove use of the 'register' storage class specifier
-  - remove "yyscanner" argument from these methods:
-      yy_fatal_error, cmExpr_yyalloc, cmExpr_yyrealloc, cmExpr_yyfree
-  - remove all YY_BREAK lines occurring right after return statements
-  - change while ( 1 ) to for(;;)
-
-Modify cmExprLexer.h:
-  - remove TABs
-  - remove the yy_init_globals function
-  - remove the block that includes unistd.h
-  - remove #line directives (avoids bogus warning on old Sun)
+  - remove trailing whitespace: sed -i 's/\s*$//' cmExprLexer.h cmExprLexer.cxx
+  - remove blank lines at end of file
+  - #include "cmStandardLexer.h" at the top
+  - add cast in yy_scan_bytes for loop condition of _yybytes_len to size_t
 
 */
 
-#include "cmStandardLexer.h"
+/* IWYU pragma: no_forward_declare yyguts_t */
 
 #include "cmExprParserHelper.h"