Various changes post sorting out some of the issues regarding task ordering.

test0 cannot be the first task in the list as it must have a prior physical_base.lds in order to create test_exec_linker.lds.
mm0 appears to have to precede fs0 for the tests to execute on start.  This should be considered a bug.

SConstruct

@@ -34,7 +34,7 @@ cml2CompileRulesFile = buildDirectory + '/cml2Rules.out'
 cml2ConfigPropertiesFile = buildDirectory + '/cml2Config.out'
 cml2ConfigHeaderFile = buildDirectory + '/cml2Config.h'
 
-configureHelpEntry = 'configure the build.'
+configureHelpEntry = 'configure the build. This must be done before any other action is possible.'
 
 #  The choice of which parts of the kernel to compile and include in the build depends on the configuration
 #  which is managed using CML2.  CML2 uses a base configuration file (currently #configs/arm.cml) to drive

containers/SConscript

@@ -50,7 +50,7 @@ def buildTask(programName, sources, environment, previousImage, extraCppPath=Non
     Depends(objects, e['configFiles'])
     program = e.Program(programName, objects)
     environment['physicalBaseLinkerScript'] = Command('physical_base.lds', previousImage, 'tools/pyelf/readelf.py --first-free-page ' + previousImage[0].path + ' >> $TARGET')
-    Depends(program, [environment['physicalBaseLinkerScript']])
+    Depends(program, environment['physicalBaseLinkerScript'])
     return program
 
 tasksEnvironment = environment.Clone()
@@ -67,12 +67,25 @@ tasksEnvironment['posixServicesDirectory'] = 'containers/' + posixServicesDirect
 ####  TODO: Why does the linker require crt0.o to be in the current directory and named as such.  Is it
 ####  because of the text in the linker script?
 ####
-    
-#### taskNameList = [ f.name for f in Glob(posixServicesDirectory + '*') if f.name not in taskLibraryNames + ['bootdesc'] ]
-#### imageOrderData = [(taskName, []) for taskName in taskNameList]
 
-#  Have to know the build is in build/containers, can't use '#' here.
+## If the ordering of tasks is not important then we should just be able to pull in all non-library
+## directories that are not bootdesc.  If there needs to be a policy then either the directory names need to
+## provide an order or a policy file presenting an order is needed.  For now we have a policy file.  Since
+## we need to guarantee the ordering across many containers and many builds.
+
+## taskNameList = [ f.name for f in Glob(posixServicesDirectory + '*') if f.name not in taskLibraryNames + ['bootdesc'] ]
+## imageOrderData = [(taskName, []) for taskName in taskNameList]
+
+#  To get the policy file, we have to know the build is being executed in the build/containers directory,
+#  and that we can't use '#' as this is Python not SCons.
+
+####
+####  TODO: Task order (mm0, fs0, test0) works, but no other order does.  This implies a bug in the SCons
+####  code.
+####
+
 execfile('../../containers/' + posixServicesDirectory + '/taskOrder.py')
+
 imageOrderData = [(taskName, []) for taskName in taskOrder]
 imageOrderData[0][1].append(startAxf)
 tasks = []

containers/posix/taskOrder.py

@@ -20,10 +20,12 @@
 # A sequence determining the order of tasks in the packing.
 
 ####
-####  TODO: Why do the tests only run when the load order is mm0, fs0, test0 -- any other order and the tests
-####  do not run.  Worse if test0 is not last then there are problems with the compilation du to issues with
-####  linker scripts.
+####  TODO: Why do the tests only run when mm0 precedes fs0 in the load list?
 ####
 
-taskOrder = ('mm0', 'fs0', 'test0')
-#taskOrder = ('fs0', 'mm0', 'test0')
+# NB test0 cannot be the first task in the list because of the processing of test_exec_linker.lds.in.
+
+#taskOrder = ('mm0', 'fs0', 'test0')#  Works fine.
+#taskOrder = ('fs0', 'mm0', 'test0')#  Compiles, loads and executes fine, but does not execute the tests.
+#taskOrder = ('fs0', 'test0', 'mm0')#  Compiles, loads and executes fine, but does not execute the tests.
+taskOrder = ('mm0', 'test0', 'fs0')#  Works fine.

containers/posix/test0/SConscript

@@ -36,6 +36,16 @@ def createTestExecS(target, source, env):
 .align 4
 ''' % ( source[0].path ))
 
+try:
+    environment['physicalBaseLinkerScript']
+except KeyError:
+    print '''
+####
+####  The test0 task cannot be the first task in the list of tasks.
+####
+'''
+    Exit ( 1 )
+
 testTaskEnvironment = environment.Clone()
 testTaskEnvironment.Append(CPPPATH=['#' + testTaskEnvironment['posixServicesDirectory'] +'/libposix/include/posix'])
 testExecLinkerScript = Command('#build/' + testTaskEnvironment['posixServicesDirectory'] +'/' + taskName + '/test_exec_linker.lds', ['test_exec_linker.lds.in', testTaskEnvironment['physicalBaseLinkerScript']], createTestExecLinkerScript)