[commit: ghc] ghc-8.4: Correct -g flag description (2df499b)

[git at git.haskell.org]

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

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/2df499b429fd5bbe0f72b56948b9fc2161ec9b4c/ghc

>---------------------------------------------------------------

commit 2df499b429fd5bbe0f72b56948b9fc2161ec9b4c
Author: Bartosz Nitka <niteria at gmail.com>
Date:   Mon Mar 5 15:14:36 2018 -0500

    Correct -g flag description
    
    Since 7aaeaf81ea95c36fe1dc4da449cf6092a792fd09
    `-g1` and `-g2` are actually different.
    The tutorial below is correct.
    
    Test Plan: harbormaster
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4471
    
    (cherry picked from commit 5b1132eefd0a75189b3527486b492c3dffc7bdf1)


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2df499b429fd5bbe0f72b56948b9fc2161ec9b4c
 docs/users_guide/debug-info.rst | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/docs/users_guide/debug-info.rst b/docs/users_guide/debug-info.rst
index 915591a..0b8cb5e 100644
--- a/docs/users_guide/debug-info.rst
+++ b/docs/users_guide/debug-info.rst
@@ -17,8 +17,9 @@ useable by most UNIX debugging tools.
 
     Emit debug information in object code. Currently only DWARF debug
     information is supported on x86-64 and i386. Currently debug levels 0
-    through 3 are accepted, with 0 disabling debug information production.
-    Levels 1 through 3 are functionally equivalent.
+    through 3 are accepted, with 0 disabling debug information production
+    and higher numbers producing richer output. If ⟨n⟩ is omitted level 2
+    is assumed.
 
 
 Tutorial