[commit: ghc] master: Document default value of +RTS -N in user's guide (23f6f31)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/23f6f31dd66d7c370cb8beec3f1d96a0cb577393/ghc

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commit 23f6f31dd66d7c370cb8beec3f1d96a0cb577393
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Fri Aug 17 10:56:28 2018 +0300

    Document default value of +RTS -N in user's guide
    
    Summary: (This is documented in `+RTS -?` but wasn't documented in the user's guide)
    
    Reviewers: simonmar, bgamari, monoidal
    
    Reviewed By: monoidal
    
    Subscribers: rwbarton, carter
    
    Differential Revision: https://phabricator.haskell.org/D5065


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23f6f31dd66d7c370cb8beec3f1d96a0cb577393
 docs/users_guide/using-concurrent.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docs/users_guide/using-concurrent.rst b/docs/users_guide/using-concurrent.rst
index e8640dc..da27708 100644
--- a/docs/users_guide/using-concurrent.rst
+++ b/docs/users_guide/using-concurrent.rst
@@ -133,6 +133,8 @@ use the RTS :rts-flag:`-N ⟨x⟩` options.
     value of ⟨x⟩ itself based on how many processors are in your
     machine.
 
+    Omitting ``-N⟨x⟩`` entirely means ``-N1``.
+
     With ``-maxN⟨x⟩``, i.e. ``+RTS -maxN3 -RTS``, the runtime will choose
     at most (x), also limited by the number of processors on the system.
     Omitting (x) is an error, if you need a default use option ``-N``.