re PR c/81854 (weak alias of an incompatible symbol accepted)

libstdc++/ChangeLog:

	PR c/81854
	* src/c++98/compatibility.cc (_GLIBCXX_3_4_SYMVER): Declare alias
	target as a C++ function with no prototype.
	(_GLIBCXX_3_4_5_SYMVER): Ditto.

From-SVN: r251211

libstdc++-v3/ChangeLog

+2017-08-20  Martin Sebor  <msebor@redhat.com>
+
+	PR c/81854
+	* src/c++98/compatibility.cc (_GLIBCXX_3_4_SYMVER): Declare alias
+	target as a C++ function with no prototype.
+	(_GLIBCXX_3_4_5_SYMVER): Ditto.
+
 2017-08-20  John David Anglin  <danglin@gcc.gnu.org>
 
 	PR testsuite/81056

libstdc++-v3/src/c++98/compatibility.cc

@@ -367,13 +367,13 @@ _GLIBCXX_END_NAMESPACE_VERSION
 
 #define _GLIBCXX_3_4_SYMVER(XXname, name) \
    extern "C" void \
-   _X##name() \
+   _X##name(...) \
    __attribute__ ((alias(#XXname))); \
    asm (".symver " "_X" #name "," #name "@GLIBCXX_3.4");
 
 #define _GLIBCXX_3_4_5_SYMVER(XXname, name) \
    extern "C" void \
-   _Y##name() \
+   _Y##name(...) \
    __attribute__ ((alias(#XXname))); \
    asm (".symver " "_Y" #name  "," #name "@@GLIBCXX_3.4.5");