How to use pprTrace ?

[Omar Mefire]

Hi all,I'm trying to step through some ghc code.I am trying to use pprTrace ( for the first time ) and I keep getting an error when I use it :I've added it to the file ghc/Main.hs and the resulting code is this :
       let argv1' = map (mkGeneralLocated "on the commandline") argv1       (argv2, staticFlagWarnings) <- pprTrace "argv1 prime" (ppr argv1') $ parseStaticFlags argv1'
I want to examine the value of argv1'. After my modification, I go into the ghc/ folder and run : 'make'But doing this leads to an error when I try to run the program :
      ghc-stage2: panic! (the 'impossible' happened)      (GHC version 7.11.20150810 for x86_64-unknown-linux): Static flags have not been initialised!          Please call GHC.parseStaticFlags early enough.
What am I doing wrong ? Omar Mefire, 
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