libbsd/libbsd-symver.patch

diff --git a/configure.ac b/configure.ac
index 6e9496d..abf891e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -96,7 +96,7 @@ AC_CACHE_CHECK(
 [[
 static int rc = 1;
 static void init(int argc) { if (argc == 1) rc = 0; }
-void (*init_func)(int argc) __attribute__((__section__(".init_array"))) = init;
+__attribute__ ((used)) void (*init_func)(int argc) __attribute__((__section__(".init_array"))) = init;
 int main() { return rc; }
 ]]
 		)],
@@ -183,4 +183,13 @@ AC_CONFIG_FILES([
 	test/Makefile
 ])
 AC_CONFIG_HEADERS([config.h])
+
+# GCC tries to be "helpful" and only issue a warning for unrecognized
+# attributes.  So we compile the test with Werror, so that if the
+# attribute is not recognized the compilation fails
+AC_LANG(C)
+AC_LANG_WERROR
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([[__attribute__ ((symver ("foo@foo_1"))) void frob (void) { }]])],
+                  [AC_DEFINE([HAVE_ATTRIBUTE_SYMVER], [1], [Checking for symver attribute])], [])
+
 AC_OUTPUT
diff --git a/src/local-link.h b/src/local-link.h
index 0d4351a..5f98656 100644
--- a/src/local-link.h
+++ b/src/local-link.h
@@ -32,16 +32,22 @@
 		__attribute__((__used__,__section__(".gnu.warning." #symbol))) = msg;
 
 #ifdef __ELF__
-#define libbsd_symver_default(alias, symbol, version) \
-	__asm__(".symver " #symbol "," #alias "@@" #version)
-
-#define libbsd_symver_variant(alias, symbol, version) \
-	__asm__(".symver " #symbol "," #alias "@" #version)
+# if HAVE_ATTRIBUTE_SYMVER
+#  define libbsd_symver_default(alias, symbol, version) \
+	__attribute__ ((symver (#alias "@@" #version)))
+#  define libbsd_symver_variant(alias, symbol, version) \
+	__attribute__ ((symver (#alias "@" #version)))
+# else
+#  define libbsd_symver_default(alias, symbol, version) \
+	__asm__(".symver " #symbol "," #alias "@@" #version);
+#  define libbsd_symver_variant(alias, symbol, version) \
+	__asm__(".symver " #symbol "," #alias "@" #version);
+# endif
 #else
-#define libbsd_symver_default(alias, symbol, version) \
+# define libbsd_symver_default(alias, symbol, version) \
 	extern __typeof(symbol) alias __attribute__((__alias__(#symbol)))
 
-#define libbsd_symver_variant(alias, symbol, version)
+# define libbsd_symver_variant(alias, symbol, version)
 #endif
 
 #endif
diff --git a/src/setproctitle.c b/src/setproctitle.c
index ff32aa3..f8ede26 100644
--- a/src/setproctitle.c
+++ b/src/setproctitle.c
@@ -222,6 +222,7 @@ setproctitle_init(int argc, char *argv[], char *envp[])
 #define SPT_MAXTITLE 255
 #endif
 
+libbsd_symver_default(setproctitle, setproctitle_impl, LIBBSD_0.5)
 void
 setproctitle_impl(const char *fmt, ...)
 {
@@ -281,7 +282,6 @@ setproctitle_impl(const char *fmt, ...)
 		*++nul = '\0';
 	}
 }
-libbsd_symver_default(setproctitle, setproctitle_impl, LIBBSD_0.5);
 
 /* The original function introduced in 0.2 was a stub, it only got implemented
  * in 0.5, make the implementation available in the old version as an alias
@@ -289,11 +289,12 @@ libbsd_symver_default(setproctitle, setproctitle_impl, LIBBSD_0.5);
  * new version, so that new code depends on the implemented version. */
 #ifdef HAVE_TYPEOF
 extern __typeof__(setproctitle_impl)
+libbsd_symver_variant(setproctitle, setproctitle_stub, LIBBSD_0.2)
 setproctitle_stub
 	__attribute__((__alias__("setproctitle_impl")));
 #else
 void
+libbsd_symver_variant(setproctitle, setproctitle_stub, LIBBSD_0.2)
 setproctitle_stub(const char *fmt, ...)
 	__attribute__((__alias__("setproctitle_impl")));
 #endif
-libbsd_symver_variant(setproctitle, setproctitle_stub, LIBBSD_0.2);
diff --git a/src/unvis.c b/src/unvis.c
index 166421a..218ec47 100644
--- a/src/unvis.c
+++ b/src/unvis.c
@@ -563,16 +563,16 @@ strunvis(char *dst, const char *src)
  * OpenBSD, 2001: strnunvis(char *dst, const char *src, size_t dlen);
  * NetBSD: 2012,  strnunvis(char *dst, size_t dlen, const char *src);
  */
+libbsd_symver_default(strnunvis, strnunvis_openbsd, LIBBSD_0.2)
 ssize_t
 strnunvis_openbsd(char *dst, const char *src, size_t dlen)
 {
 	return strnunvisx(dst, dlen, src, 0);
 }
-libbsd_symver_default(strnunvis, strnunvis_openbsd, LIBBSD_0.2);
 
+libbsd_symver_variant(strnunvis, strnunvis_netbsd, LIBBSD_0.9.1)
 int
 strnunvis_netbsd(char *dst, size_t dlen, const char *src)
 {
 	return strnunvisx(dst, dlen, src, 0);
 }
-libbsd_symver_variant(strnunvis, strnunvis_netbsd, LIBBSD_0.9.1);
diff --git a/src/vis.c b/src/vis.c
index c8e5ae8..254f209 100644
--- a/src/vis.c
+++ b/src/vis.c
@@ -732,19 +732,19 @@ strvis(char *mbdst, const char *mbsrc, int flags)
  * OpenBSD, 2001: strnvis(char *dst, const char *src, size_t dlen, int flag);
  * NetBSD: 2012,  strnvis(char *dst, size_t dlen, const char *src, int flag);
  */
+libbsd_symver_default(strnvis, strnvis_openbsd, LIBBSD_0.2)
 int
 strnvis_openbsd(char *mbdst, const char *mbsrc, size_t dlen, int flags)
 {
 	return istrsenvisxl(mbdst, &dlen, mbsrc, flags, "", NULL);
 }
-libbsd_symver_default(strnvis, strnvis_openbsd, LIBBSD_0.2);
 
+libbsd_symver_variant(strnvis, strnvis_netbsd, LIBBSD_0.9.1)
 int
 strnvis_netbsd(char *mbdst, size_t dlen, const char *mbsrc, int flags)
 {
 	return istrsenvisxl(mbdst, &dlen, mbsrc, flags, "", NULL);
 }
-libbsd_symver_variant(strnvis, strnvis_netbsd, LIBBSD_0.9.1);
 
 int
 stravis(char **mbdstp, const char *mbsrc, int flags)
diff --git a/test/nlist.c b/test/nlist.c
index 82e24e9..0bfdb46 100644
--- a/test/nlist.c
+++ b/test/nlist.c
@@ -38,14 +38,15 @@ extern int data_pub_init;
 extern int data_pub_uninit[2048];
 extern int *data_pub_ptr;
 
-int *data_pub_ptr = &data_prv_init;
-int data_pub_init = 10;
-int data_pub_uninit[2048];
+__attribute__ ((used)) int *data_pub_ptr = &data_prv_init;
+__attribute__ ((used)) int data_pub_init = 10;
+__attribute__ ((used)) int data_pub_uninit[2048];
 
 extern int
 func_pub(void);
 
 int
+__attribute__ ((used))
 func_pub(void)
 {
 	return 42;