Fix -Os ferror_unlocked linknamespace, localplt issues (bug 15105, bug 19463).

Continuing the fixes for linknamespace and localplt test failures with
-Os that arise from functions not being inlined in that case, this
patch fixes such failures for ferror_unlocked.

The usual approach is followed of adding __ferror_unlocked (inlined
when ferror_unlocked is), making calls use it when required for
namespace reasons (only one such call), and using libc_hidden_proto /
libc_hidden_weak for the ferror_unlocked weak alias when only localplt
but not namespace issues are involved.

Tested for x86_64 (both without -Os to make sure that case continues
to work, and with -Os to make sure all the relevant linknamespace and
localplt test failures are resolved).  Because of other such failures
that remain after this patch, neither of the bugs can yet be closed.

	[BZ #15105]
	[BZ #19463]
	* libio/ferror_u.c (ferror_unlocked): Rename to __ferror_unlocked
	and define as weak alias of __ferror_unlocked.  Use
	libc_hidden_weak.
	* include/stdio.h [!_ISOMAC] (ferror_unlocked): Use
	libc_hidden_proto.
	[!_ISOMAC] (__ferror_unlocked) New declaration, and inline
	function if [__USE_EXTERN_INLINES].
	* time/getdate.c (__getdate_r): Call __ferror_unlocked instead of
	ferror_unlocked.

1 files changed, 14 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 35bf20a..de48635 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2018-02-19  Joseph Myers  <joseph@codesourcery.com>
+
+	[BZ #15105]
+	[BZ #19463]
+	* libio/ferror_u.c (ferror_unlocked): Rename to __ferror_unlocked
+	and define as weak alias of __ferror_unlocked.  Use
+	libc_hidden_weak.
+	* include/stdio.h [!_ISOMAC] (ferror_unlocked): Use
+	libc_hidden_proto.
+	[!_ISOMAC] (__ferror_unlocked) New declaration, and inline
+	function if [__USE_EXTERN_INLINES].
+	* time/getdate.c (__getdate_r): Call __ferror_unlocked instead of
+	ferror_unlocked.
+
 2018-02-19  Rical Jasan  <ricaljasan@pacific.net>
 
 	[BZ #6889]