Add 32-bit version of llvm-allocated-type.

README.chromium

 Name: The LLVM/Clang compiler modified to intercept allocated type
 Short Name: llvm-allocated-type
 URL: http://llvm.org/
 Version: 0
 Revision: 167488
 License: University of Illinois Open Source License
 License File: LICENSE.TXT
 Security Critical: no
 
 Description:
 LLVM is a compiler infrastructure.
 Clang is a C, C++, Objective C and Objective C++ front-end for LLVM.
 
 Local Modifications:
 This package consists of a locally modified version of Clang.  It instruments
 code around 'new' and 'delete' expressions to skim allocated types and sizes.
 
 The difference from the original Clang is in allocated-type.patch.
 
 Usage:
 The feature is enabled by a compiler option "-fintercept-allocation-function".
 With the option, Clang automatically includes <typeinfo> and declares following
 two functions in each compiled source file:
 - void* __op_new_intercept__(void*, size_t, const std::type_info&)
 - void* __op_delete_intercept__(void*, size_t, const std::type_info&)
 
 Then, Clang inserts a call for one of these functions in every new/delete
 expressions as below.
 
-operator new(...) calls are replaced to 
-=> __op_new_intercept__(operator new(...), size, type) 
+operator new(...) calls are replaced to
+=> __op_new_intercept__(operator new(...), size, type)
 
-operator delete(ptr [, size]) calls are replaced to 
-=> operator delete(__op_delete_intercept__(ptr, size, type) [, size]) 
+operator delete(ptr [, size]) calls are replaced to
+=> operator delete(__op_delete_intercept__(ptr, size, type) [, size])
+
+Note:
+32-bit Clang is officially unsupported.  The 32-bit Clang in Linux_ia32/ is
+specially prepared only for comparing 32-bit and 64-bit memory usage.  Any
+failure by this compiler should not close the tree.