Re: Problem with e_flex in base

[Andrew Johnson <anj@aps.anl.gov>]

Mark Rivers wrote:
> I believe I used WinZip to extract the archive, rather than tar.

That at least explains where the line endings got changed.

> I don't think I like your proposed solution for the following reasons:
>
> - EPICS is supposed to build for multiple architectures from the same
> source tree.  If I use WinZip to extract EPICS base it builds fine for
> WIN32.  However, if I later decide I also want to build for Cygwin, I
> can't use that same source tree.

If you try to build a tree that has DOS line endings using the SUNWspro 
compiler on Solaris, it does fail.  Consider this C construct, which is 
used in various places in base:

#define macro \
	multi-line \
	macro being \
	defined here

The Solaris C preprocessor takes the first back-slash to be escaping the 
following <cr>, and the <lf> immediately following it to be the end of 
the macro definition.  It also reports the following warning on every 
single #include line it sees:

	warning: invalid white space character in directive

Thus it is not reasonable to expect *all* architectures to build from 
the exact same source tree.

> - Even if I untar the source file with Cygwin tar, if I then use a
> Windows text editor, such as Wordpad, to edit any .l file (in base or in
> any application), e_flex fails.

Unless you configure Cygwin to use DOS line endings, which should fix 
the problem for *every* C program automatically since it modifies the 
behaviour of the C runtime library.  Do you have some particular 
objection to doing that?  I'm not a Cygwin/Windows user, so I don't know 
if there's a downside to it.

> - Most, if not all, other EPICS code that reads ASCII files (.adl files,
> .db files, .dbd files, etc.) are now tolerant of either type of line
> terminator.  e_flex seems to be the exception.

GCC also seems to have bowed under pressure so it also accepts the above 
macro without complaint, even on Unix systems.  I guess this is one of 
those "be liberal in what you accept" situations, so I'll commit the 
changes.

Flex is third party software and is pretty complex, written using 
itself.  I believe that my changes are correct, but they will need to be 
tested.

- Andrew
--
There is no S in exprexxo.