Make -dtrace-level a dynamic flag

compiler/main/DynFlags.hs

@@ -616,6 +616,7 @@ data DynFlags = DynFlags {
 
   -- Output style options
   pprUserLength         :: Int,
+  traceLevel            :: Int, -- Standard level is 1. Less verbose is 0.
 
   -- | what kind of {-# SCC #-} to add automatically
   profAuto              :: ProfAuto,
@@ -974,6 +975,7 @@ defaultDynFlags mySettings =
         flushOut = defaultFlushOut,
         flushErr = defaultFlushErr,
         pprUserLength = 5,
+        traceLevel = 1,
         profAuto = NoProfAuto,
         llvmVersion = panic "defaultDynFlags: No llvmVersion"
       }
@@ -1618,6 +1620,7 @@ dynamic_flags = [
 
         ------ Output style options -----------------------------------------
   , Flag "dppr-user-length" (intSuffix (\n d -> d{ pprUserLength = n }))
+  , Flag "dtrace-level"     (intSuffix (\n d -> d{ traceLevel = n }))
 
         ------ Debugging ----------------------------------------------------
   , Flag "dstg-stats"     (NoArg (setDynFlag Opt_StgStats))

compiler/main/StaticFlags.hs

@@ -28,7 +28,7 @@ module StaticFlags (
 
 	-- Output style options
 	opt_PprCols,
-	opt_PprStyle_Debug, opt_TraceLevel,
+	opt_PprStyle_Debug,
         opt_NoDebugOutput,
 
 	-- Suppressing boring aspects of core dumps
@@ -266,10 +266,6 @@ opt_PprCols
 opt_PprStyle_Debug  :: Bool
 opt_PprStyle_Debug              = lookUp  (fsLit "-dppr-debug")
 
-opt_TraceLevel :: Int
-opt_TraceLevel = lookup_def_int "-dtrace-level" 1  	-- Standard level is 1
-	       	 			    	        -- Less verbose is 0
-
 opt_Fuel            :: Int
 opt_Fuel                        = lookup_def_int "-dopt-fuel" maxBound
 

compiler/typecheck/TcRnMonad.lhs

@@ -432,9 +432,9 @@ traceTc = traceTcN 1
 
 traceTcN :: Int -> String -> SDoc -> TcRn ()
 traceTcN level herald doc
-  | level <= opt_TraceLevel = traceOptTcRn Opt_D_dump_tc_trace $
-                              hang (text herald) 2 doc
-  | otherwise               = return ()
+    = do dflags <- getDynFlags
+         when (level <= traceLevel dflags) $
+             traceOptTcRn Opt_D_dump_tc_trace $ hang (text herald) 2 doc
 
 traceRn, traceSplice :: SDoc -> TcRn ()
 traceRn      = traceOptTcRn Opt_D_dump_rn_trace

compiler/vectorise/Vectorise/Monad/Base.hs

@@ -34,7 +34,6 @@ import TcRnMonad
 import ErrUtils
 import Outputable
 import DynFlags
-import StaticFlags
 
 import Control.Monad
 
@@ -125,10 +124,9 @@ emitVt herald doc
 --
 traceVt :: String -> SDoc -> VM () 
 traceVt herald doc
-  | 1 <= opt_TraceLevel = liftDs $
-                            traceOptIf Opt_D_dump_vt_trace $
-                              hang (text herald) 2 doc
-  | otherwise           = return ()
+  = do dflags <- getDynFlags
+       when (1 <= traceLevel dflags) $
+           liftDs $ traceOptIf Opt_D_dump_vt_trace $ hang (text herald) 2 doc
 
 -- |Dump the given program conditionally.
 --