scons: make RUBY a regular (non-global) sticky var

and force it to True for builds that imply Ruby protocols
(else unexpected things happen when testing these builds
with RUBY=False).

SConstruct

@@ -314,7 +314,6 @@ global_sticky_vars.AddVariables(
     ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
     ('EXTRAS', 'Add Extra directories to the compilation', '',
      PathListAllExist, PathListMakeAbsolute),
-    BoolVariable('RUBY', 'Build with Ruby', False),
     )
 
 # base help text
@@ -688,6 +687,7 @@ sticky_vars.AddVariables(
     BoolVariable('USE_FENV', 'Use <fenv.h> IEEE mode control', have_fenv),
     BoolVariable('USE_CHECKER', 'Use checker for detailed CPU models', False),
     BoolVariable('CP_ANNOTATE', 'Enable critical path annotation capability', False),
+    BoolVariable('RUBY', 'Build with Ruby', False),
     )
 
 nonsticky_vars.AddVariables(

build_opts/ALPHA_SE_MESI_CMP_directory

@@ -2,3 +2,4 @@ FULL_SYSTEM = 0
 SS_COMPATIBLE_FP = 1
 CPU_MODELS = 'AtomicSimpleCPU,TimingSimpleCPU,O3CPU,InOrderCPU'
 PROTOCOL = 'MESI_CMP_directory'
+RUBY = True

build_opts/ALPHA_SE_MOESI_CMP_directory

@@ -2,3 +2,4 @@ FULL_SYSTEM = 0
 SS_COMPATIBLE_FP = 1
 CPU_MODELS = 'AtomicSimpleCPU,TimingSimpleCPU,O3CPU,InOrderCPU'
 PROTOCOL = 'MOESI_CMP_directory'
+RUBY = True

build_opts/ALPHA_SE_MOESI_CMP_token

@@ -2,3 +2,4 @@ FULL_SYSTEM = 0
 SS_COMPATIBLE_FP = 1
 CPU_MODELS = 'AtomicSimpleCPU,TimingSimpleCPU,O3CPU,InOrderCPU'
 PROTOCOL = 'MOESI_CMP_token'
+RUBY = True

build_opts/ALPHA_SE_MOESI_hammer

@@ -2,3 +2,4 @@ FULL_SYSTEM = 0
 SS_COMPATIBLE_FP = 1
 CPU_MODELS = 'AtomicSimpleCPU,TimingSimpleCPU,O3CPU,InOrderCPU'
 PROTOCOL = 'MOESI_hammer'
+RUBY = True

src/mem/ruby/SConsopts

@@ -30,9 +30,6 @@
 
 Import('*')
 
-if not main['RUBY']:
-    Return()
-
 sticky_vars.AddVariables(
     BoolVariable('NO_VECTOR_BOUNDS_CHECKS', "Don't do bounds checks", True),
     BoolVariable('RUBY_DEBUG', "Add debugging stuff to Ruby", False),