When a function takes a variable number of pointer arguments, with a zero

pointer marking the end of the list, the zero *must* be cast to the pointer
type.  An un-cast zero is a 32-bit int, and at least on x86_64, gcc will
not extend the zero to 64 bits, thus allowing the upper 32 bits to be
random junk.

The new END_WITH_NULL macro may be used to annotate a such a function
so that GCC (version 4 or newer) will detect the use of un-casted zero
at compile time.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23888 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 5 insertions, 3 deletions

diff --git a/lib/Transforms/Instrumentation/ProfilePaths/EdgeCode.cpp b/lib/Transforms/Instrumentation/ProfilePaths/EdgeCode.cpp
index 95822df002..bf94943788 100644
--- a/lib/Transforms/Instrumentation/ProfilePaths/EdgeCode.cpp
+++ b/lib/Transforms/Instrumentation/ProfilePaths/EdgeCode.cpp
@@ -40,7 +40,7 @@ static void getTriggerCode(Module *M, BasicBlock *BB, int MethNo, Value *pathNo,
   const Type *PIntTy = PointerType::get(Type::IntTy);
   Function *trigMeth = M->getOrInsertFunction("trigger", Type::VoidTy,
                                               Type::IntTy, Type::IntTy,
-                                              PIntTy, PIntTy, 0);
+                                              PIntTy, PIntTy, (Type *)0);
   assert(trigMeth && "trigger method could not be inserted!");
 
   vector<Value *> trargs;
diff --git a/lib/Transforms/Instrumentation/ProfilePaths/InstLoops.cpp b/lib/Transforms/Instrumentation/ProfilePaths/InstLoops.cpp
index 860b57f7e4..020388f2b6 100644
--- a/lib/Transforms/Instrumentation/ProfilePaths/InstLoops.cpp
+++ b/lib/Transforms/Instrumentation/ProfilePaths/InstLoops.cpp
@@ -156,7 +156,8 @@ void InstLoops::findAndInstrumentBackEdges(Function &F){
 }
 
 bool InstLoops::doInitialization (Module &M) {
-  inCountMth = M.getOrInsertFunction("llvm_first_trigger", Type::VoidTy, 0);
+  inCountMth = M.getOrInsertFunction("llvm_first_trigger", Type::VoidTy,
+                                     (Type *)0);
   return true;  // Module was modified.
 }
 
diff --git a/lib/Transforms/Instrumentation/ProfilePaths/ProfilePaths.cpp b/lib/Transforms/Instrumentation/ProfilePaths/ProfilePaths.cpp
index d0d0f550fe..ce9e328c27 100644
--- a/lib/Transforms/Instrumentation/ProfilePaths/ProfilePaths.cpp
+++ b/lib/Transforms/Instrumentation/ProfilePaths/ProfilePaths.cpp
@@ -189,7 +189,8 @@ bool ProfilePaths::runOnFunction(Function &F){
     // IN THEIR INITIALIZE METHOD!!
     Function *initialize =
       F.getParent()->getOrInsertFunction("reoptimizerInitialize", Type::VoidTy,
-                                         PointerType::get(Type::IntTy), 0);
+                                         PointerType::get(Type::IntTy),
+                                         (Type *)0);
 
     std::vector<Value *> trargs;
     trargs.push_back(threshold);