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ARM: Compiler bug; omitted subexpression

This code:

unsigned int Argh( unsigned int Word, unsigned int Base )
{
  return ( ( Word & ~1 ) << 2 ) + Base;
}

is compiled as:

                  Argh PROC
;;;1      unsigned int Argh( unsigned int Word, unsigned int Base )
;;;2      {
000000  e1a02000          MOV      r2,r0
;;;3        return ( ( Word & ~1 ) << 2 ) + Base;
000004  e0810102          ADD      r0,r1,r2,LSL #2
;;;4      }
000008  e12fff1e          BX       lr
;;;5
                          ENDP

The subexpression involving & has been omitted. Simpler variants (omitting either the shift or the addition) compile correctly, for example:

                  Argh4 PROC
;;;18     unsigned int Argh4( unsigned int Word )
;;;19     {
000030  e1a01000          MOV      r1,r0
;;;20       return ( Word & ~1 ) << 2;
000034  e3c10001          BIC      r0,r1,#1
000038  e1a00100          LSL      r0,r0,#2
;;;21     }
00003c  e12fff1e          BX       lr
                          ENDP

Inserting a temporary variable to receive the & is not sufficient to work around.

I'm using

IDE-Version:
ÂµVision3 V3.60
Copyright (c) Keil Elektronik GmbH / Keil Software, Inc. 1995 - 2008

[[[snip]]]

Tool Version Numbers:
Toolchain:        RealView MDK BASIC (256K)  Version: 3.20
Toolchain Path:    BIN31\ 
C Compiler:         Armcc.Exe       V3.1.0.919
Assembler:          Armasm.Exe       V3.1.0.919
Linker/Locator:     ArmLink.Exe       V3.1.0.919
Librarian:             ArmAr.Exe       V3.1.0.919
Hex Converter:      FromElf.Exe       V3.1.0.919
CPU DLL:               SARM.DLL       V3.20
Dialog DLL:         DARMST9.DLL       V1.03
Target DLL:             BIN\UL2ARM.DLL       V1.37
Dialog DLL:         TARMST9.DLL       V1.01a

I've looked at release notes for newer versions, but see nothing that looks relevant.