--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,20 @@
+2012-12-22  Paul Eggert  <eggert@cs.ucla.edu>
+
+	argp: port new 'inline' approach to Sun C 5.12 + Solaris 10
+	On this platform, we are not optimizing but we are using
+	the substitute for extern inlines, so compile as if
+	C99-style extern inline, or a substitute, is available.
+	* lib/argp-fmtstream.h (argp_fmtstream_set_lmargin)
+	(__argp_fmtstream_set_lmargin, argp_fmtstream_set_rmargin)
+	(__argp_fmtstream_set_rmargin, argp_fmtstream_set_wmargin)
+	(__argp_fmtstream_set_wmargin, argp_fmtstream_point)
+	(__argp_fmtstream_point) [!_LIBC && !__OPTIMIZE__]:
+	Declare as ARGP_FS_EI, not as extern.
+	* lib/argp.h (argp_usage, __argp_usage, _option_is_short)
+	(__option_is_short, _option_is_end, __option_is_end)
+	[!_LIBC && __USE_EXTERN_INLINES]:
+	Declare as ARGP_EI, not as extern.
+
 2012-12-21  Paul Eggert  <eggert@cs.ucla.edu>
 
 	AC_PROG_MKDIR_P: port workaround to pre-2.62 Autoconf

--- a/lib/argp-fmtstream.h
+++ b/lib/argp-fmtstream.h
@@ -154,7 +154,7 @@
 #define __argp_fmtstream_rmargin argp_fmtstream_rmargin
 #define __argp_fmtstream_wmargin argp_fmtstream_wmargin
 
-#if _LIBC || !defined __OPTIMIZE__
+#if _LIBC
 /* Set __FS's left margin to LMARGIN and return the old value.  */
 extern size_t argp_fmtstream_set_lmargin (argp_fmtstream_t __fs,
                                           size_t __lmargin);
@@ -184,7 +184,7 @@
 extern int _argp_fmtstream_ensure (argp_fmtstream_t __fs, size_t __amount);
 extern int __argp_fmtstream_ensure (argp_fmtstream_t __fs, size_t __amount);
 
-#ifdef __OPTIMIZE__
+#if !_LIBC || defined __OPTIMIZE__
 /* Inline versions of above routines.  */
 
 #if !_LIBC
@@ -352,7 +352,7 @@
 _GL_INLINE_HEADER_END
 #endif
 
-#endif /* __OPTIMIZE__ */
+#endif /* !_LIBC || __OPTIMIZE__ */
 
 #endif /* ARGP_FMTSTREAM_USE_LINEWRAP */
 

--- a/lib/argp.h
+++ b/lib/argp.h
@@ -519,7 +519,7 @@
                                FILE *__restrict __stream,
                                unsigned int __flags);
 
-#if _LIBC || !defined __USE_EXTERN_INLINES
+#if _LIBC
 /* Possibly output the standard usage message for ARGP to stderr and exit.  */
 extern void argp_usage (const struct argp_state *__state);
 extern void __argp_usage (const struct argp_state *__state);
@@ -552,7 +552,7 @@
                             const char *__restrict __fmt, ...)
      _GL_ATTRIBUTE_FORMAT ((__printf__, 4, 5));
 
-#if _LIBC || !defined __USE_EXTERN_INLINES
+#if _LIBC
 /* Returns true if the option OPT is a valid short option.  */
 extern int _option_is_short (const struct argp_option *__opt) __THROW;
 extern int __option_is_short (const struct argp_option *__opt) __THROW;
@@ -572,7 +572,7 @@
                            const struct argp_state *__restrict __state)
      __THROW;
 
-#ifdef __USE_EXTERN_INLINES
+#if !_LIBC || defined __USE_EXTERN_INLINES
 
 # if !_LIBC
 #  define __argp_usage argp_usage