Re: Additional link flags for HP aCC and SGI CC

[Ludovic Courtès]

Hello,

Today, 6 minutes, 10 seconds ago, Gary V.Vaughan wrote:
> I couldn't find -Xcompiler or -Wc in the manual...

In 1.5.6's manual, it is documented in the "Compile mode" node (in
"Invoking libtool").

> But there is also -Xcompiler for these cases.  Remember that libtool is
> supposed to hide platform specific concerns, and if we started adding
> specific support for particular compiler switches, libtool would soon
> have no advantage over using the compiler directly for developers who
> want to provide a package that compiles on several hosts.

Well, libtool already accumulates knowledge about various compilers,
linkers and so on.  So adding such switches can be seen as teaching it
about useful things it should be aware of.  ;-) 

> Does ``-Xcompiler -AA'' work for you?

Yes it does actually.

> If you can find a higher level abstraction that can be implemented for
> all platforms that libtool supports, along with a patch for the 
> platforms
> you have access to, then we can probably accept that.  E.g: libtool 
> - --abi=32,
> or libtool --threaded...

There need to be some sort of an abstraction.  I'm not sure, however,
whether it's up to Libtool to do this or not (because there may be a lot
more options than just those we're talking about).  I currently use an
Autoconf macro that determines the C++ compiler vendor, and then a set
of macros such as `AC_CXX_CXXFLAGS_STD_LANG' and
`AC_CXX_LDFLAGS_STD_LANG', etc. that augment my `CXXFLAGS', `CPPFLAGS'
and `LDFLAGS' with the particular switches that are needed to turn on
standard C++ features with this compiler.  I believe this approach is
simpler than augmenting Libtool with a plethora of very specific
options.  But anyway, this "knowledge base" about specific compiler
tricks has to be kept somewhere in such a way that people wouldn't have
to worry any longer about those specificities.

Thanks,
Ludovic.