Merge pull request #88 (for real this time). Prev commit was actually #87.

 * Allow multiple options to be specified with --debug=a,b,c
 * Add support for a readonly cache (--cache-readonly)
 * Always print stats if requested
 * Generally try harder to print out a message on build errors

1 files changed, 20 insertions, 9 deletions

diff --git a/src/engine/SCons/Script/Main.py b/src/engine/SCons/Script/Main.py
index a81ac98..7c21519 100644
--- a/src/engine/SCons/Script/Main.py
+++ b/src/engine/SCons/Script/Main.py
@@ -79,7 +79,12 @@ def fetch_win32_parallel_msg():
     import SCons.Platform.win32
     return SCons.Platform.win32.parallel_msg
 
-#
+def revert_io():
+    # This call is added to revert stderr and stdout to the original
+    # ones just in case some build rule or something else in the system
+    # has redirected them elsewhere.
+    sys.stderr = sys.__stderr__
+    sys.stdout = sys.__stdout__
 
 class SConsPrintHelpException(Exception):
     pass
@@ -272,6 +277,9 @@ class BuildTask(SCons.Taskmaster.OutOfDateTask):
                (EnvironmentError, SCons.Errors.StopError,
                             SCons.Errors.UserError))):
             type, value, trace = buildError.exc_info
+            if tb and print_stacktrace:
+                sys.stderr.write("scons: internal stack trace:\n")
+                traceback.print_tb(tb, file=sys.stderr)
             traceback.print_exception(type, value, trace)
         elif tb and print_stacktrace:
             sys.stderr.write("scons: internal stack trace:\n")
@@ -986,9 +994,9 @@ def _main(parser):
         # reading SConscript files and haven't started building
         # things yet, stop regardless of whether they used -i or -k
         # or anything else.
+        revert_io()
         sys.stderr.write("scons: *** %s  Stop.\n" % e)
-        exit_status = 2
-        sys.exit(exit_status)
+        sys.exit(2)
     global sconscript_time
     sconscript_time = time.time() - start_time
 
@@ -1074,6 +1082,8 @@ def _main(parser):
         # Build the targets
         nodes = _build_targets(fs, options, targets, target_top)
         if not nodes:
+            revert_io()
+            print 'Found nothing to build'
             exit_status = 2
 
 def _build_targets(fs, options, targets, target_top):
@@ -1093,6 +1103,7 @@ def _build_targets(fs, options, targets, target_top):
         SCons.Node.FS.set_diskcheck(options.diskcheck)
 
     SCons.CacheDir.cache_enabled = not options.cache_disable
+    SCons.CacheDir.cache_readonly = options.cache_readonly
     SCons.CacheDir.cache_debug = options.cache_debug
     SCons.CacheDir.cache_force = options.cache_force
     SCons.CacheDir.cache_show = options.cache_show
@@ -1302,12 +1313,8 @@ def _exec_main(parser, values):
         prof = Profile()
         try:
             prof.runcall(_main, parser)
-        except SConsPrintHelpException, e:
+        finally:
             prof.dump_stats(options.profile_file)
-            raise e
-        except SystemExit:
-            pass
-        prof.dump_stats(options.profile_file)
     else:
         _main(parser)
 
@@ -1345,7 +1352,10 @@ def main():
     OptionsParser = parser
 
     try:
-        _exec_main(parser, values)
+        try:
+            _exec_main(parser, values)
+        finally:
+            revert_io()
     except SystemExit, s:
         if s:
             exit_status = s
@@ -1362,6 +1372,7 @@ def main():
         parser.print_help()
         exit_status = 0
     except SCons.Errors.BuildError, e:
+        print e
         exit_status = e.exitstatus
     except:
         # An exception here is likely a builtin Python exception Python