UNIX source code errors detected by new C compiler

[jim at uw-beaver.UUCP]

    Green Hills Software, who markets a optimizing C compiler for
    68000's and NSC 16032's, claims to have discovered NUMEROUS errors
    in the 4.1 source code.  Their compiler barfed on a substantial
    portion of the UNIX section 1 and 8 commands, and they feel the
    errors detected are real even though they don't appear under the
    4.1 C compiler.

But was this lots of different errors, or the same error many times?  I
think the problem of code depending on ( *(NULL) == 0 ) is pretty well
known and has been in Unix since the beginning of time.  Of course this
wouldn't be caught by a compiler.  Less well known is that the current
C language doesn't allow multiple global definitions, but most
compilers allow them and much code depends on them.  I think it would
be nice if the compiler would accept multiple globals but issue an
error message so that this usage would go away, much as the '=+'
operator has gone away.