clang: Enable compiling gem5 using clang 2.9 and 3.0

This patch adds the necessary flags to the SConstruct and SConscript
files for compiling using clang 2.9 and later (on Ubuntu et al and OSX
XCode 4.2), and also cleans up a bunch of compiler warnings found by
clang. Most of the warnings are related to hidden virtual functions,
comparisons with unsigneds >= 0, and if-statements with empty
bodies. A number of mismatches between struct and class are also
fixed. clang 2.8 is not working as it has problems with class names
that occur in multiple namespaces (e.g. Statistics in
kernel_stats.hh).

clang has a bug (http://llvm.org/bugs/show_bug.cgi?id=7247) which
causes confusion between the container std::set and the function
Packet::set, and this is currently addressed by not including the
entire namespace std, but rather selecting e.g. "using std::vector" in
the appropriate places.

1 files changed, 6 insertions, 6 deletions

diff --git a/src/cpu/base.hh b/src/cpu/base.hh
index d4de55453..f6c0da3d3 100644
--- a/src/cpu/base.hh
+++ b/src/cpu/base.hh
@@ -61,7 +61,7 @@
 #include "arch/interrupts.hh"
 #endif
 
-class BaseCPUParams;
+struct BaseCPUParams;
 class BranchPred;
 class CheckerCPU;
 class ThreadContext;
@@ -241,16 +241,16 @@ class BaseCPU : public MemObject
     /// Notify the CPU that the indicated context is now active.  The
     /// delay parameter indicates the number of ticks to wait before
     /// executing (typically 0 or 1).
-    virtual void activateContext(int thread_num, int delay) {}
+    virtual void activateContext(ThreadID thread_num, int delay) {}
 
     /// Notify the CPU that the indicated context is now suspended.
-    virtual void suspendContext(int thread_num) {}
+    virtual void suspendContext(ThreadID thread_num) {}
 
     /// Notify the CPU that the indicated context is now deallocated.
-    virtual void deallocateContext(int thread_num) {}
+    virtual void deallocateContext(ThreadID thread_num) {}
 
     /// Notify the CPU that the indicated context is now halted.
-    virtual void haltContext(int thread_num) {}
+    virtual void haltContext(ThreadID thread_num) {}
 
    /// Given a Thread Context pointer return the thread num
    int findContext(ThreadContext *tc);
@@ -279,7 +279,7 @@ class BaseCPU : public MemObject
 
     /// Take over execution from the given CPU.  Used for warm-up and
     /// sampling.
-    virtual void takeOverFrom(BaseCPU *, Port *ic, Port *dc);
+    virtual void takeOverFrom(BaseCPU *);
 
     /**
      *  Number of threads we're actually simulating (<= SMT_MAX_THREADS).