Fix availability of symbols in other partition

[Jan Hubicka]

Hi,
get_availability incorrectly return AVAIL_AVAILABLE when symbol is in other
partition but can be interposed at runtime.  The problem is check for
DECL_EXTERNAL which is there to check for external inline functions (keyed to
other unit).  

Bootstrapped/regtested x86_64-linux, plan to push it shortly.
Honza

        PR ipa/122430

gcc/ChangeLog:

        * cgraph.cc (cgraph_node::get_availability): Fix availability of
        symbols in other partition.

gcc/testsuite/ChangeLog:

        * gcc.dg/ipa/pr122430.c: New test.

diff --git a/gcc/cgraph.cc b/gcc/cgraph.cc
index 508a5559569..13efe89ebba 100644
--- a/gcc/cgraph.cc
+++ b/gcc/cgraph.cc
@@ -2833,7 +2833,7 @@ cgraph_node::get_availability (symtab_node *ref)
      the inlinability hooks completely eliminated).  */
 
   else if (decl_replaceable_p (decl, semantic_interposition)
-          && !DECL_EXTERNAL (decl))
+          && (!DECL_EXTERNAL (decl) || in_other_partition))
     avail = AVAIL_INTERPOSABLE;
   else avail = AVAIL_AVAILABLE;
 
diff --git a/gcc/testsuite/gcc.dg/ipa/pr122430.c 
b/gcc/testsuite/gcc.dg/ipa/pr122430.c
new file mode 100644
index 00000000000..af1a1c4323d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/pr122430.c
@@ -0,0 +1,11 @@
+// { dg-do link }
+// { dg-options "-fpic -O2 -flto -flto-partition=max -fsemantic-interposition 
-shared" }
+// { dg-require-effective-target fpic }
+// { dg-require-effective-target shared }
+// { dg-require-effective-target lto } 
+void error () __attribute__ ((error  ("error")));
+int g() { return 42; }
+int f() { int v = g();
+       if (__builtin_constant_p (v))
+         error ();
+}