Typos in comments

compiler/basicTypes/RdrName.hs

@@ -1040,7 +1040,7 @@ There are two reasons for shadowing:
     hence the `mk_fake-imp_spec` in `shadowName`.  See also Note
     [Interactively-bound Ids in GHCi] in HscTypes
 
-  - Data types also have Extenal Names, like Ghci4.T; but we still want
+  - Data types also have External Names, like Ghci4.T; but we still want
     'T' to mean the newly-declared 'T', not an old one.
 
 * Nested Template Haskell declaration brackets

compiler/codeGen/StgCmmHeap.hs

@@ -149,7 +149,7 @@ emitSetDynHdr base info_ptr ccs
   where
     header :: DynFlags -> [CmmExpr]
     header dflags = [info_ptr] ++ dynProfHdr dflags ccs
-        -- ToDof: Parallel stuff
+        -- ToDo: Parallel stuff
         -- No ticky header
 
 -- Store the item (expr,off) in base[off]

compiler/coreSyn/MkCore.hs

@@ -337,7 +337,7 @@ We could do one of two things:
 * Flatten it out, so that
     mkCoreTup [e1] = e1
 
-* Built a one-tuple (see Note [One-tuples] in TysWiredIn)
+* Build a one-tuple (see Note [One-tuples] in TysWiredIn)
     mkCoreTup1 [e1] = Unit e1
   We use a suffix "1" to indicate this.
 

compiler/deSugar/Desugar.hs

@@ -247,7 +247,7 @@ Note [Top-level evidence]
 ~~~~~~~~~~~~~~~~~~~~~~~~~
 Top-level evidence bindings may be mutually recursive with the top-level value
 bindings, so we must put those in a Rec.  But we can't put them *all* in a Rec
-because the occurrence analyser doesn't teke account of type/coercion variables
+because the occurrence analyser doesn't take account of type/coercion variables
 when computing dependencies.
 
 So we pull out the type/coercion variables (which are in dependency order),
@@ -544,7 +544,7 @@ about this. For example in Control.Arrow we have
 
 and similar, which will elicit exactly these warnings, and risk never
 firing.  But it's not clear what to do instead.  We could make the
-class methocd rules inactive in phase 2, but that would delay when
+class method rules inactive in phase 2, but that would delay when
 subsequent transformations could fire.
 
 

compiler/iface/BinIface.hs

@@ -223,7 +223,7 @@ writeBinIface dflags hi_path mod_iface = do
     -- NB. write the dictionary after the symbol table, because
     -- writing the symbol table may create more dictionary entries.
 
-    -- Write the dictionary pointer at the fornt of the file
+    -- Write the dictionary pointer at the front of the file
     dict_p <- tellBin bh          -- This is where the dictionary will start
     putAt bh dict_p_p dict_p      -- Fill in the placeholder
     seekBin bh dict_p             -- Seek back to the end of the file

compiler/main/TidyPgm.hs

@@ -224,7 +224,7 @@ Plan B: include pragmas, make interfaces
 * Step 1: Figure out which Ids are externally visible
           See Note [Choosing external Ids]
 
-* Step 2: Gather the extenally visible rules, separately from
+* Step 2: Gather the externally visible rules, separately from
           the top-level bindings.
           See Note [Finding external rules]
 

compiler/simplCore/CallArity.hs

@@ -406,7 +406,7 @@ published papers on Call Arity describe it.
 
 In practice, there are thunks that do a just little work, such as
 pattern-matching on a variable, and the benefits of eta-expansion likely
-oughtweigh the cost of doing that repeatedly. Therefore, this implementation of
+outweigh the cost of doing that repeatedly. Therefore, this implementation of
 Call Arity considers everything that is not cheap (`exprIsCheap`) as a thunk.
 
 Note [Call Arity and Join Points]

compiler/simplCore/OccurAnal.hs

@@ -2088,7 +2088,7 @@ type GlobalScruts = IdSet   -- See Note [Binder swap on GlobalId scrutinees]
 --      x = (p,q)               -- Don't inline p or q
 --      y = /\a -> (p a, q a)   -- Still don't inline p or q
 --      z = f (p,q)             -- Do inline p,q; it may make a rule fire
--- So OccEncl tells enought about the context to know what to do when
+-- So OccEncl tells enough about the context to know what to do when
 -- we encounter a constructor application or PAP.
 
 data OccEncl

compiler/typecheck/TcPatSyn.hs

@@ -360,7 +360,7 @@ Here 'k' is implicitly bound in the signature, but (with
 -XScopedTypeVariables) it does still scope over the pattern-synonym
 definition.  But what about 'kk', which is oexistential?  It too is
 implicitly bound in the signature; should it too scope?  And if so,
-what type varaible is it bound to?
+what type variable is it bound to?
 
 The trouble is that the type variable to which it is bound is itself
 only brought into scope in part the pattern, so it makes no sense for

compiler/typecheck/TcSMonad.hs

@@ -870,7 +870,7 @@ The idea is that
     (NB: we could strengten K1) in this way too, but see K3.
 
   - (K2b): If this holds then, by (T2), b is not in t.  So applying the
-    work item does not genenerate any new opportunities for applying S
+    work item does not generate any new opportunities for applying S
 
   - (K2c): If this holds, we can't pass through this triple infinitely
     often, because if we did then fs>=f, fw>=f, hence by (R2)

compiler/typecheck/TcSimplify.hs

@@ -1098,7 +1098,7 @@ decideQuantifiedTyVars mono_tvs name_taus psigs candidates
        ; return (qtvs, co_vars) }
          -- Return all the CoVars that (transitively) might be mentioned
          -- in the tau_tys etc.  We don't need to do a closeOverKinds on
-         -- co_vars to get the transitive ones, becuase the grown_tvs
+         -- co_vars to get the transitive ones, because the grown_tvs
          -- are already closed over kinds, and hence contain all such
          -- co_vars
 

mk/warnings.mk

@@ -11,8 +11,8 @@ SRC_HC_OPTS     += -Wall
 SRC_HC_OPTS_STAGE1 += $(WERROR)
 SRC_HC_OPTS_STAGE2 += $(WERROR)
 
-# Enable -Wcpp-undef for GHC components only as we don't (currently) expect core
-# libraries to build in this configuration (see #13636).
+# Enable -Wcpp-undef for GHC components only, as we don't (currently) expect
+# core libraries to build in this configuration (see #13636).
 GhcRtsHcOpts    += -Wcpp-undef
 GhcStage1HcOpts += -Wcpp-undef
 GhcStage2HcOpts += -Wcpp-undef