ruby/ruby.h: remove unnecessary exports from C-API

Needlessly exporting can reduce performance locally and increase
binary size.

Increasing the footprint of our C-API larger is also detrimental
to our development as it encourages tighter coupling with our
internals; making it harder for us to preserve compatibility.

If some parts of the core codebase needs access to globals,
internal.h should be used instead of anything in include/ruby/*.

"Urabe, Shyouhei" <shyouhei@ruby-lang.org> wrote:
> On Thu, Jan 18, 2018 at 7:33 PM, Eric Wong <normalperson@yhbt.net> wrote:
> > shyouhei@ruby-lang.org wrote:
> >>   https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=61908
> >>
> >>     export rb_mFConst
> >
> > Why are we exporting all these and making the public C-API bigger?
> > If anything, we should make these static.  Thanks.
>
> No concrete reason, except they have already been externed in 2.5.
> These variables had lacked declarations so far, which resulted in their
> visibility to be that of extern. The commit is just confirming the status quo.
>
> I'm not against to turn them into static.

This reverts changes from r61910, r61909, r61908, r61907, and r61906.

* transcode.c (rb_eUndefinedConversionError): make static
  (rb_eInvalidByteSequenceError): ditto
  (rb_eConverterNotFoundError): ditto
* process.c (rb_mProcGID, rb_mProcUid, rb_mProcID_Syscall): ditto
* file.c (rb_mFConst): ditto
* error.c (rb_mWarning, rb_cWarningBuffer): ditto
* enumerator.c (rb_cLazy): ditto
  [Misc #14381]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62029 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

transcode.c

@@ -17,9 +17,9 @@
 #define ENABLE_ECONV_NEWLINE_OPTION 1
 
 /* VALUE rb_cEncoding = rb_define_class("Encoding", rb_cObject); */
-VALUE rb_eUndefinedConversionError;
-VALUE rb_eInvalidByteSequenceError;
-VALUE rb_eConverterNotFoundError;
+static VALUE rb_eUndefinedConversionError;
+static VALUE rb_eInvalidByteSequenceError;
+static VALUE rb_eConverterNotFoundError;
 
 VALUE rb_cEncodingConverter;