[xsd-users] -Wconversion warnings

[Boris Kolpackov]

Hi Benjamin,

Benjamin Schindler <bschindler at inf.ethz.ch> writes:

> We just turned on -Wconversion warnings in our xsd-using project and it
> generated a huge numbers of warnings from libxsd, but they are all at
> the same place. Could they be fixed please?
> 
> libxsd/xsd/cxx/tree/date-time-ostream.txx:31:13: warning: conversion to
> ‘short int’ from ‘int’ may alter its value

Here is the line that this error points to:

h = -h;

The 'h' variable is declared as short. I am not sure I would like to
"fix" this since it will just make the code uglier and less readable.
All other places are very similar. Plus, if you turn -Wsign-conversion,
you get a lot more of these warnings.

Don't you also get a lot of such warnings from other libraries that
you use? For example, I get quite a few from the Xerces-C++ headers.

I think the best option, at least for XSD, would be to disable these
warnings for the generated/libxsd code, as Balasubramanyam suggested.
Unfortunately, GCC does not provide the necessary mechanism until
version 4.6 (not yet released; adds #pragma GCC diagnostic push/pop).
We can cleanly disable the warnings starting from this version but
I am not sure whether this will help you.

The only other option that I can think of is to install XSD into
a separate directory and use the -isystem option instead of -I
to specify the libxsd include directory. This will make GCC treat
the libxsd headers as system headers and suppress all the warnings
in them.

Boris