diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index f03e1f931032..1a07a86f80cf 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -198,6 +198,16 @@ Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
     if (SemaBuiltinLongjmp(TheCall))
       return ExprError();
     break;
+  case Builtin::BI__builtin_constant_p:
+    if (TheCall->getNumArgs() == 0)
+      return Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args)
+        << 0 /*function call*/ << 1 << 0 << TheCall->getSourceRange();
+    if (TheCall->getNumArgs() > 1)
+      return Diag(TheCall->getArg(1)->getLocStart(),
+                  diag::err_typecheck_call_too_many_args)
+        << 0 /*function call*/ << 1 << TheCall->getNumArgs()
+        << TheCall->getArg(1)->getSourceRange();
+    break;
   case Builtin::BI__sync_fetch_and_add:
   case Builtin::BI__sync_fetch_and_sub:
   case Builtin::BI__sync_fetch_and_or:
diff --git a/clang/test/Sema/builtins.c b/clang/test/Sema/builtins.c
index 21a1f72e1d5f..7f284dabcd54 100644
--- a/clang/test/Sema/builtins.c
+++ b/clang/test/Sema/builtins.c
@@ -95,3 +95,10 @@ void test14() {
 void test15(const char *s) {
   __builtin_printf("string is %s\n", s);
 }
+
+// PR7885
+int test16() {
+  return __builtin_constant_p() + // expected-error{{too few arguments}}
+         __builtin_constant_p(1, 2); // expected-error {{too many arguments}}
+}
+  
diff --git a/clang/test/Sema/const-eval.c b/clang/test/Sema/const-eval.c
index 42097e75f317..9f2d32769fb3 100644
--- a/clang/test/Sema/const-eval.c
+++ b/clang/test/Sema/const-eval.c
@@ -41,7 +41,7 @@ struct s {
 
 EVAL_EXPR(19, ((int)&*(char*)10 == 10 ? 1 : -1));
 
-EVAL_EXPR(20, __builtin_constant_p(*((int*) 10), -1, 1));
+EVAL_EXPR(20, __builtin_constant_p(*((int*) 10)));
 
 EVAL_EXPR(21, (__imag__ 2i) == 2 ? 1 : -1);