debug builds of mysql-5.6.6-m9 with gcc 4.7.1 fail

[Rich Prohaska]

Hello,

A debug build of mysql-5.6.6-m9 using gcc 4.7.1 on centos 5.8 hits a
bunch of narrowing conversion errors.

Here is an example:

mysql-5.6.6-m9/plugin/semisync/semisync.cc:30:40: warning: narrowing
conversion of =91239u=92 from =91const unsigned char=92 to =91const
char=92= inside { } is ill-formed in C++11 [-Wnarrowing]

There are lots of others.

We added "-Wno-error=3Dnarrowing" to the COMMON_C_FLAGS and
COMMON_CXX_FLAGS to get a debug build to build without errors.

Rich Prohaska