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

1 files changed, 3 insertions, 3 deletions

diff --git a/lib/Bytecode/Reader/ReaderWrappers.cpp b/lib/Bytecode/Reader/ReaderWrappers.cpp
index 4db954a307..1ee27185ad 100644
--- a/lib/Bytecode/Reader/ReaderWrappers.cpp
+++ b/lib/Bytecode/Reader/ReaderWrappers.cpp
@@ -181,7 +181,7 @@ static ModuleProvider* CheckVarargs(ModuleProvider* MP) {
     const Type* ArgTy = F->getFunctionType()->getReturnType();
     const Type* ArgTyPtr = PointerType::get(ArgTy);
     Function* NF = M->getOrInsertFunction("llvm.va_start",
-                                               RetTy, ArgTyPtr, 0);
+                                          RetTy, ArgTyPtr, (Type *)0);
 
     for(Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E;)
       if (CallInst* CI = dyn_cast<CallInst>(*I++)) {
@@ -204,7 +204,7 @@ static ModuleProvider* CheckVarargs(ModuleProvider* MP) {
     const Type* ArgTy = F->getFunctionType()->getParamType(0);
     const Type* ArgTyPtr = PointerType::get(ArgTy);
     Function* NF = M->getOrInsertFunction("llvm.va_end",
-                                                 RetTy, ArgTyPtr, 0);
+                                          RetTy, ArgTyPtr, (Type *)0);
 
     for(Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E;)
       if (CallInst* CI = dyn_cast<CallInst>(*I++)) {
@@ -230,7 +230,7 @@ static ModuleProvider* CheckVarargs(ModuleProvider* MP) {
     const Type* ArgTy = F->getFunctionType()->getReturnType();
     const Type* ArgTyPtr = PointerType::get(ArgTy);
     Function* NF = M->getOrInsertFunction("llvm.va_copy",
-                                          RetTy, ArgTyPtr, ArgTyPtr, 0);
+                                          RetTy, ArgTyPtr, ArgTyPtr, (Type *)0);
 
     for(Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E;)
       if (CallInst* CI = dyn_cast<CallInst>(*I++)) {