PR45267: Don't reject pure-specifiers with escaped newlines in their '0' token.

clang/lib/Parse/ParseDeclCXX.cpp

@@ -2670,7 +2670,7 @@ Parser::ParseCXXClassMemberDeclaration(AccessSpecifier AS,
 
     auto &Zero = NextToken();
     SmallString<8> Buffer;
-    if (Zero.isNot(tok::numeric_constant) || Zero.getLength() != 1 ||
+    if (Zero.isNot(tok::numeric_constant) ||
         PP.getSpelling(Zero, Buffer) != "0")
       return false;
 

clang/test/Parser/cxx-class.cpp

@@ -37,7 +37,9 @@ public:
   virtual int vf5a(){0;}; // function definition, expected-warning {{unused}}
   virtual int vf6()(0); // expected-error +{{}} expected-note +{{}}
   virtual int vf7() = { 0 }; // expected-error {{does not look like a pure-specifier}}
-  
+  virtual int PR45267() = \
+                        0; // ok, despite escaped newline
+
 private:
   int x,f(),y,g();
   inline int h();