Parse: Don't crash on trailing whitespace before EOF

Parser::ParseDeclarationSpecifiers eagerly updates the source range of
the DeclSpec with the current token position.  However, it might not
consume any more tokens.

Fix this by only setting the start of the range, not the end.  This way
the SourceRange will be invalid if we don't consume any more tokens.

This fixes PR20413.

Differential Revision: http://reviews.llvm.org/D4646

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@214018 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 1bbc8943372500f84efd45f140a9e9c4689b8069..727915c5a6c1cce980cae54a3f6381f49701f5fd 100644 (file)
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -2449,8 +2449,11 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
                                         DeclSpecContext DSContext,
                                         LateParsedAttrList *LateAttrs) {
   if (DS.getSourceRange().isInvalid()) {
+    // Start the range at the current token but make the end of the range
+    // invalid.  This will make the entire range invalid unless we successfully
+    // consume a token.
     DS.SetRangeStart(Tok.getLocation());
-    DS.SetRangeEnd(Tok.getLocation());
+    DS.SetRangeEnd(SourceLocation());
   }
 
   bool EnteringContext = (DSContext == DSC_class || DSContext == DSC_top_level);

diff --git a/test/Parser/eof2.cpp b/test/Parser/eof2.cpp
new file mode 100644 (file)
index 0000000..6a8b862
--- /dev/null
+++ b/test/Parser/eof2.cpp
@@ -0,0 +1,15 @@
+// RUN: not %clang_cc1 %s -fsyntax-only 2>&1 | FileCheck %s
+
+// CHECK: error: expected expression
+// CHECK: error: expected member name or ';' after declaration specifiers
+// CHECK: error: expected '}'
+// CHECK: note: to match this '{'
+// CHECK: error: expected ';' after class
+// CHECK: 4 errors generated.
+
+// Do not add anything to the end of this file.  This requires the whitespace
+// plus EOF after the '<' token.
+
+template <typename T>
+class a {
+  a<