[bitc-dev] Build Problem with DoxyLexer.l

[James Graves]

On Mon, Feb 20, 2006 at 05:27:20PM -0500, Jonathan S. Shapiro wrote:

> What architecture are you compiling for?

32-bit x86.

> On our machines, we are using flex 2.5.4. Since your version is later
> I'm wondering if something got broken in later versions of flex. Looking
> at the output being generated here, yy_push_state is definitely not
> defined twice by my flex.
> 
> Since the highest version of flex known to FSF is flex-2.5.4a, I find
> the "2.5.31" version number a bit suspicious...

The 2.5.4a release is from 1997, BTW.  I don't know where exactly the
2.5.31 upstream is coming from in Debian.

It looks like they are deliberately breaking backwards compatibility
with the newer versions of flex.  There is an old-flex package I can
try, which is based on the 2.5.4a release.

Here's the /usr/share/doc/flex/NEWS.Debian.gz file for the recent
version:

flex (2.5.31-17) unstable; urgency=low

 * This version of Flex is a major upgrade from previous versions. There
   have been extensive changes. These changes require source changes in
   lex input files.  The new direction flex is taking is to incorporate
   new functionality at the expense of POSIX or backward
   compatibility. This can also be considered part of the gcc migration
   process; flex has been updated (the buggy, rickety set of patches
   required to make it work with gcc was dumped in favour of a well
   engineered upstream migration).
 * Flex scanners are now reenterant, you may have multiple scanners in
   the same program with differing sets of defaults, and they play
   nicer with modern C and C++ compilers. C++ scanners are compatible
   with recent c++ compilers (conform to ANSI C++, gcc 3.2), supports
   bison variables yylval and yylloc. Some variables have been
   renamed. Flex generates C99 defs now, see YY_TRADITIONAL_FUNC_DEFS.
   yylineno is present in all scanners. yylineno is per-buffer in
   reentrant scanners. Flex tries its best to output only the relevant
   portions of the skeleton when generating a scanner, thus avoiding as
   much conditional compilation as possible
 * The signature of all functions has changed. flex has new command line
   options, and option parsing has changed (now also supports POSIX
   conventions optionally). Handles POSIXLY_CORRECT environment
   variable.  Various i18n translations are included in the
   distribution. Flex now works with recent bison versions.  The new
   scanners do not polllute the global name space, and thus macros that
   used to be available to user code are no longer present.
 * Flex has gained an extensive new test suite run at build time to test
   for regressions.
 * The flip side is that Flex no longer conforms to the POSIX lex
   behaviour, and the scanners require conforming implementations when
   flex is used in ANSI C mode. Flex has broken backwards
   compatibility. This is not a bug, but done deliberately, by
   design. 
 * The package flex-old provides the same behaviour as version 2.5.4a of
   Flex.
 * Please make sure you are prepared for these changes in Flex
   before continuing with its upgrade.

 -- Manoj Srivastava <srivasta at debian.org>  Fri, 31 Oct 2003 21:53:16 -0600

James Graves