gcc49 fails to build on Yosemite 10.10.1

[David Nicholls]

Yosemite 10.10.1, Xcode 6.1 (with command line tools installed as part of it)

The error:

--->  Building gcc49
Error: org.macports.build for port gcc49 returned: command execution failed
Please see the log file for port gcc49 for details:

The log file is 4.9 Meg in size. 

The first error in the log relating to this appears to be:

:info:build /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_gcc49/gcc49/work/gcc-4.9.2/libgcc/../gcc/tsystem.h:87:19: fatal error: stdio.h: No such file or directory

Is this a known problem?  I was able to install gcc48 with no trouble.

This is a completely clean install.  All references to the previous (Mavericks) install of Macports were removed.

Following the error message instructions, I did a "sudo port clean gcc49" and re-ran the install.  Same result.

I'm logging a bug report, which will be similar to this message.

DN