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, 8 insertions, 7 deletions

diff --git a/lib/Transforms/IPO/LowerSetJmp.cpp b/lib/Transforms/IPO/LowerSetJmp.cpp
index c040025115..9dd9501f1c 100644
--- a/lib/Transforms/IPO/LowerSetJmp.cpp
+++ b/lib/Transforms/IPO/LowerSetJmp.cpp
@@ -204,32 +204,33 @@ bool LowerSetJmp::doInitialization(Module& M)
 
   // void __llvm_sjljeh_init_setjmpmap(void**)
   InitSJMap = M.getOrInsertFunction("__llvm_sjljeh_init_setjmpmap",
-                                    Type::VoidTy, SBPPTy, NULL);
+                                    Type::VoidTy, SBPPTy, (Type *)0);
   // void __llvm_sjljeh_destroy_setjmpmap(void**)
   DestroySJMap = M.getOrInsertFunction("__llvm_sjljeh_destroy_setjmpmap",
-                                       Type::VoidTy, SBPPTy, NULL);
+                                       Type::VoidTy, SBPPTy, (Type *)0);
 
   // void __llvm_sjljeh_add_setjmp_to_map(void**, void*, unsigned)
   AddSJToMap = M.getOrInsertFunction("__llvm_sjljeh_add_setjmp_to_map",
                                      Type::VoidTy, SBPPTy, SBPTy,
-                                     Type::UIntTy, NULL);
+                                     Type::UIntTy, (Type *)0);
 
   // void __llvm_sjljeh_throw_longjmp(int*, int)
   ThrowLongJmp = M.getOrInsertFunction("__llvm_sjljeh_throw_longjmp",
-                                       Type::VoidTy, SBPTy, Type::IntTy, NULL);
+                                       Type::VoidTy, SBPTy, Type::IntTy,
+                                       (Type *)0);
 
   // unsigned __llvm_sjljeh_try_catching_longjmp_exception(void **)
   TryCatchLJ =
     M.getOrInsertFunction("__llvm_sjljeh_try_catching_longjmp_exception",
-                          Type::UIntTy, SBPPTy, NULL);
+                          Type::UIntTy, SBPPTy, (Type *)0);
 
   // bool __llvm_sjljeh_is_longjmp_exception()
   IsLJException = M.getOrInsertFunction("__llvm_sjljeh_is_longjmp_exception",
-                                        Type::BoolTy, NULL);
+                                        Type::BoolTy, (Type *)0);
 
   // int __llvm_sjljeh_get_longjmp_value()
   GetLJValue = M.getOrInsertFunction("__llvm_sjljeh_get_longjmp_value",
-                                     Type::IntTy, NULL);
+                                     Type::IntTy, (Type *)0);
   return true;
 }