In file make/bsd/makefiles/gcc.make - the optimization level specified for unsafe.cpp is -01 instead of -O1.

In file make/bsd/makefiles/gcc.make the following comment is incorrect:

    # There are some files which don't like precompiled headers
    # The following files are build with 'OPT_CFLAGS/NOOPT' (-O0) in the opt build.
    # But Clang doesn't support a precompiled header which was compiled with -O3
    # to be used in a compilation unit which uses '-O0'. We could also prepare an
    # extra '-O0' PCH file for the opt build and use it here, but it's probably
    # not worth the effort as long as only two files need this special handling.

Needs to be updated to reflect:

- Not all files in the list are compiled with 'OPT_CFLAGS/NOOPT'.

- The precompiled header may be compiled with -O3 or -Os depending on the setting of 'OPT_CFLAGS_DEFAULT'.

- This is not just an issue between the compilation of -O0 and -O3. The issue is more general. When USE_CLANG is true, if the PCH file is compiled at a higher optimization level, (-Os or -O3), than the C++ file, (-O0 thru -O2), the following compile time error message is generated.
error: __OPTIMIZE_SIZE__ predefined macro was enabled in PCH file but is currently disabled

- The last sentence should be updated, because since the files in the list are not all compiled with -O0, the solution would only solve the issue for some of the files but not all.