Fix 2 cases of uninitialized reads of an invalid PresumedLoc.

The code in CGExpr was added back in 2012 (r165536) but not exercised in tests
until recently.

Detected on the MemorySanitizer bootstrap bot.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@190521 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index 12aa0a2b7c43614e31768747d58eba7e8a1e31fb..89340b4db8247a85baee901331d90002806c5739 100644 (file)
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -2095,8 +2095,8 @@ llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
     PLoc.isValid() ? cast<llvm::Constant>(
                        Builder.CreateGlobalStringPtr(PLoc.getFilename()))
                    : llvm::Constant::getNullValue(Int8PtrTy),
-    Builder.getInt32(PLoc.getLine()),
-    Builder.getInt32(PLoc.getColumn())
+    Builder.getInt32(PLoc.isValid() ? PLoc.getLine() : 0),
+    Builder.getInt32(PLoc.isValid() ? PLoc.getColumn() : 0)
   };
 
   return llvm::ConstantStruct::getAnon(Data);

diff --git a/tools/libclang/CXSourceLocation.cpp b/tools/libclang/CXSourceLocation.cpp
index a33c9d4f26995fd86af7b3382387205fafe3a9d2..64b2908c49da0b647e0af1a7bdcca97a9b3c6c4d 100644 (file)
--- a/tools/libclang/CXSourceLocation.cpp
+++ b/tools/libclang/CXSourceLocation.cpp
@@ -266,7 +266,7 @@ void clang_getPresumedLocation(CXSourceLocation location,
                                CXString *filename,
                                unsigned *line,
                                unsigned *column) {
-  
+
   if (!isASTUnitSourceLocation(location)) {
     // Other SourceLocation implementations do not support presumed locations
     // at this time.
@@ -276,20 +276,22 @@ void clang_getPresumedLocation(CXSourceLocation location,
 
   SourceLocation Loc = SourceLocation::getFromRawEncoding(location.int_data);
 
-  if (!location.ptr_data[0] || Loc.isInvalid())
+  if (!location.ptr_data[0] || Loc.isInvalid()) {
     createNullLocation(filename, line, column);
-  else {
-    const SourceManager &SM =
-    *static_cast<const SourceManager*>(location.ptr_data[0]);
-    PresumedLoc PreLoc = SM.getPresumedLoc(Loc);
-    
-    if (filename)
-      *filename = cxstring::createRef(PreLoc.getFilename());
-    if (line)
-      *line = PreLoc.getLine();
-    if (column)
-      *column = PreLoc.getColumn();
+    return;
   }
+
+  const SourceManager &SM =
+      *static_cast<const SourceManager *>(location.ptr_data[0]);
+  PresumedLoc PreLoc = SM.getPresumedLoc(Loc);
+  if (PreLoc.isInvalid()) {
+    createNullLocation(filename, line, column);
+    return;
+  }
+
+  if (filename) *filename = cxstring::createRef(PreLoc.getFilename());
+  if (line) *line = PreLoc.getLine();
+  if (column) *column = PreLoc.getColumn();
 }
 
 void clang_getInstantiationLocation(CXSourceLocation location,