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.
llvm-svn: 23888
diff --git a/llvm/lib/Transforms/IPO/SimplifyLibCalls.cpp b/llvm/lib/Transforms/IPO/SimplifyLibCalls.cpp
index 58aac20..63ab333 100644
--- a/llvm/lib/Transforms/IPO/SimplifyLibCalls.cpp
+++ b/llvm/lib/Transforms/IPO/SimplifyLibCalls.cpp
@@ -311,7 +311,8 @@
if (!memcpy_func) {
const Type *SBP = PointerType::get(Type::SByteTy);
memcpy_func = M->getOrInsertFunction("llvm.memcpy", Type::VoidTy,SBP, SBP,
- Type::UIntTy, Type::UIntTy, 0);
+ Type::UIntTy, Type::UIntTy,
+ (Type *)0);
}
return memcpy_func;
}
@@ -319,7 +320,7 @@
Function* get_floorf() {
if (!floorf_func)
floorf_func = M->getOrInsertFunction("floorf", Type::FloatTy,
- Type::FloatTy, 0);
+ Type::FloatTy, (Type *)0);
return floorf_func;
}