Re: Exception handling in clang

[Pete French]

> I've just committed initial support for 'zero-cost' exception handling  
> in clang.  Currently this only works for @finally and for @catch'ing  
> id types (I plan on fixing that limitation soon).  I'd appreciate it  
> if anyone who has code which uses exceptions could test this.  The  
> support should currently be enough for anything using NS_DURING and  
> friends to compile with zero-cost exceptions, rather than setjmp/ 
> longjmp.

Is this in the llvm/clang svn tree ? I've been trying to do an update
and get this compiled today (revision 71215), but it fails for me:

llvm[4]: Compiling ASTContext.cpp for Debug build 
In file included from 
/usr/home/petefrench/llvm-clang/llvm/tools/clang/lib/AST/../../include/clang/AST/DeclBase.h:18,
                 from 
/usr/home/petefrench/llvm-clang/llvm/tools/clang/lib/AST/../../include/clang/AST/Decl.h:17,
                 from 
/usr/home/petefrench/llvm-clang/llvm/tools/clang/lib/AST/../../include/clang/AST/ASTContext.h:21,
                 from ASTContext.cpp:14:
/usr/home/petefrench/llvm-clang/llvm/include/llvm/ADT/PointerIntPair.h: In 
instantiation of 'llvm::PointerIntPair<clang::Type*, 3u, unsigned int, 
llvm::PointerLikeTypeTraits<clang::Type*> >':
/usr/home/petefrench/llvm-clang/llvm/tools/clang/lib/AST/../../include/clang/AST/Type.h:76:
   instantiated from here
/usr/home/petefrench/llvm-clang/llvm/include/llvm/ADT/PointerIntPair.h:43: 
warning: left shift count >= width of type
/usr/home/petefrench/llvm-clang/llvm/include/llvm/ADT/PointerIntPair.h:43: 
error: overflow in constant expression
/usr/home/petefrench/llvm-clang/llvm/include/llvm/ADT/PointerIntPair.h: In 
member function 'IntType llvm::PointerIntPair<PointerTy, IntBits, IntType, 
PtrTraits>::getInt() const [with PointerTy = clang::Type*, unsigned int IntBits 
= 3u, IntType = unsigned int, PtrTraits = 
llvm::PointerLikeTypeTraits<clang::Type*>]':
/usr/home/petefrench/llvm-clang/llvm/tools/clang/lib/AST/../../include/clang/AST/Type.h:96:
   instantiated from here
/usr/home/petefrench/llvm-clang/llvm/include/llvm/ADT/PointerIntPair.h:72: 
warning: right shift count >= width of type
/usr/home/petefrench/llvm-clang/llvm/include/llvm/ADT/PointerIntPair.h: In 
member function 'void llvm::PointerIntPair<PointerTy, IntBits, IntType, 
PtrTraits>::setInt(IntType) [with PointerTy = clang::Type*, unsigned int 
IntBits = 3u, IntType = unsigned int, PtrTraits = 
llvm::PointerLikeTypeTraits<clang::Type*>]':
/usr/home/petefrench/llvm-clang/llvm/tools/clang/lib/AST/../../include/clang/AST/Type.h:97:
   instantiated from here
/usr/home/petefrench/llvm-clang/llvm/include/llvm/ADT/PointerIntPair.h:88: 
warning: overflow in implicit constant conversion
/usr/home/petefrench/llvm-clang/llvm/include/llvm/ADT/PointerIntPair.h:89: 
warning: left shift count >= width of type
gmake[4]: *** 
[/usr/home/petefrench/llvm-clang/llvm/tools/clang/lib/AST/Debug/ASTContext.o] 
Error 1

-pete.