RFR (S): 8143215: gcc 4.1.2: fix three issues breaking the build.

[Kim Barrett]

On Nov 18, 2015, at 3:31 PM, Lindenmaier, Goetz <goetz.lindenmaier at sap.com> wrote:
> 
> Yes, this is because the warnings are enabled, and -Werror is set.
> I had to do similar changes on a regular basis before, and I don't want to 
> question support of gcc 4.1.2 and the corresponding flags each time.

OK, that helps.  But is it specifically -Wconversion, or is there some
other warning involved?

Assuming it is -Wconversion that is causing this and similar issues, I
suggest the real (and ongoing) problem is the use of that flag.

The meaning of that flag was changed in gcc4.3 to something that the
hotspot code base is *really* not prepared for.

Before gcc4.3 it was a mechanism for detecting differences that would
arise between code that had prototypes and code that didn't.  Well,
that's just not an issue.  So I suggest there is no benefit to
enabling this warning.  And if it is leading to build failures with
old versions of gcc, then I suggest that enabling it is actively
harmful.