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.

4 files changed, 26 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 35bf20ac11..de48635f3f 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]
diff --git a/include/stdio.h b/include/stdio.h
index 7871000071..1bf49a92b5 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -185,6 +185,8 @@ extern __typeof (fputs_unlocked) __fputs_unlocked;
 libc_hidden_proto (__fputs_unlocked)
 libc_hidden_proto (feof_unlocked)
 extern __typeof (feof_unlocked) __feof_unlocked attribute_hidden;
+libc_hidden_proto (ferror_unlocked)
+extern __typeof (ferror_unlocked) __ferror_unlocked attribute_hidden;
 libc_hidden_proto (fmemopen)
 /* The prototype needs repeating instead of using __typeof to use
    __THROW in C++ tests.  */
@@ -211,6 +213,12 @@ __NTH (__feof_unlocked (FILE *__stream))
 {
   return __feof_unlocked_body (__stream);
 }
+
+__extern_inline int
+__NTH (__ferror_unlocked (FILE *__stream))
+{
+  return __ferror_unlocked_body (__stream);
+}
 #  endif
 
 # endif /* not _ISOMAC */
diff --git a/libio/ferror_u.c b/libio/ferror_u.c
index afd0bef225..3eaf84e074 100644
--- a/libio/ferror_u.c
+++ b/libio/ferror_u.c
@@ -30,8 +30,10 @@
 #undef ferror_unlocked
 
 int
-ferror_unlocked (_IO_FILE *fp)
+__ferror_unlocked (_IO_FILE *fp)
 {
   CHECK_FILE (fp, EOF);
   return _IO_ferror_unlocked (fp);
 }
+weak_alias (__ferror_unlocked, ferror_unlocked)
+libc_hidden_weak (ferror_unlocked)
diff --git a/time/getdate.c b/time/getdate.c
index 29ad760c29..e568149cdf 100644
--- a/time/getdate.c
+++ b/time/getdate.c
@@ -206,7 +206,7 @@ __getdate_r (const char *string, struct tm *tp)
   free (line);
 
   /* Check for errors. */
-  if (ferror_unlocked (fp))
+  if (__ferror_unlocked (fp))
     {
       fclose (fp);
       return 5;