[v3] Fix / clean-up config vs crosses (2/n)

[Paolo Carlini]

Hi,

this is the 2nd installment, which I'm finishing testing and mean to commit in 1-2 days. Please have a look. Basically, I'm doing 2 rather simple things: 1- Some existing tests can be changed to use TRY_COMPILE and thus run unconditionally; 2- Different sets of AC_CHECK_HEADERS are scattered around in the configurations for native and for crosses, I think a common set can be safely run unconditionally.

Paolo.

///////////////
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: CL_config_2.txt
URL: <http://gcc.gnu.org/pipermail/libstdc++/attachments/20080816/b5e304a6/attachment.txt>
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: patch_config_2.txt
URL: <http://gcc.gnu.org/pipermail/libstdc++/attachments/20080816/b5e304a6/attachment-0001.txt>