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, 5 deletions

diff --git a/src/cpu/o3/cpu.cc b/src/cpu/o3/cpu.cc
index 49843ee9b..cede7ae18 100644
--- a/src/cpu/o3/cpu.cc
+++ b/src/cpu/o3/cpu.cc
@@ -76,7 +76,7 @@
 #include "debug/Activity.hh"
 #endif
 
-class BaseCPUParams;
+struct BaseCPUParams;
 
 using namespace TheISA;
 using namespace std;
@@ -766,7 +766,8 @@ FullO3CPU<Impl>::activateContext(ThreadID tid, int delay)
 
 template <class Impl>
 bool
-FullO3CPU<Impl>::deallocateContext(ThreadID tid, bool remove, int delay)
+FullO3CPU<Impl>::scheduleDeallocateContext(ThreadID tid, bool remove,
+                                           int delay)
 {
     // Schedule removal of thread data from CPU
     if (delay){
@@ -787,7 +788,7 @@ void
 FullO3CPU<Impl>::suspendContext(ThreadID tid)
 {
     DPRINTF(O3CPU,"[tid: %i]: Suspending Thread Context.\n", tid);
-    bool deallocated = deallocateContext(tid, false, 1);
+    bool deallocated = scheduleDeallocateContext(tid, false, 1);
     // If this was the last thread then unschedule the tick event.
     if ((activeThreads.size() == 1 && !deallocated) ||
         activeThreads.size() == 0)
@@ -804,7 +805,7 @@ FullO3CPU<Impl>::haltContext(ThreadID tid)
 {
     //For now, this is the same as deallocate
     DPRINTF(O3CPU,"[tid:%i]: Halt Context called. Deallocating", tid);
-    deallocateContext(tid, true, 1);
+    scheduleDeallocateContext(tid, true, 1);
 }
 
 template <class Impl>
@@ -1230,7 +1231,7 @@ FullO3CPU<Impl>::takeOverFrom(BaseCPU *oldCPU)
 
     activityRec.reset();
 
-    BaseCPU::takeOverFrom(oldCPU, &icachePort, &dcachePort);
+    BaseCPU::takeOverFrom(oldCPU);
 
     fetch.takeOverFrom();
     decode.takeOverFrom();