diff options
Diffstat (limited to 'libraries/base/GHC/Base.hs')
| -rw-r--r-- | libraries/base/GHC/Base.hs | 43 |
1 files changed, 21 insertions, 22 deletions
diff --git a/libraries/base/GHC/Base.hs b/libraries/base/GHC/Base.hs index b496bac35e..e344f842df 100644 --- a/libraries/base/GHC/Base.hs +++ b/libraries/base/GHC/Base.hs @@ -121,8 +121,7 @@ import GHC.Maybe import {-# SOURCE #-} GHC.IO (mkUserError, mplusIO) import GHC.Tuple () -- Note [Depend on GHC.Tuple] -import GHC.Integer () -- Note [Depend on GHC.Integer] -import GHC.Natural () -- Note [Depend on GHC.Natural] +import GHC.Num.Integer () -- Note [Depend on GHC.Num.Integer] -- for 'class Semigroup' import {-# SOURCE #-} GHC.Real (Integral) @@ -144,30 +143,33 @@ infixl 4 <*>, <*, *>, <**> default () -- Double isn't available yet {- -Note [Depend on GHC.Integer] -~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -The Integer type is special because GHC.Iface.Tidy uses -GHC.Integer.Type.mkInteger to construct Integer literal values -Currently it reads the interface file whether or not the current -module *has* any Integer literals, so it's important that -GHC.Integer.Type (in package integer-gmp or integer-simple) is -compiled before any other module. (There's a hack in GHC to disable -this for packages ghc-prim, integer-gmp, integer-simple, which aren't -allowed to contain any Integer literals.) - -Likewise we implicitly need Integer when deriving things like Eq -instances. +Note [Depend on GHC.Num.Integer] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The Integer type is special because GHC.Iface.Tidy uses constructors in +GHC.Num.Integer to construct Integer literal values. Currently it reads the +interface file whether or not the current module *has* any Integer literals, so +it's important that GHC.Num.Integer is compiled before any other module. + +(There's a hack in GHC to disable this for packages ghc-prim and ghc-bignum +which aren't allowed to contain any Integer literals.) + +Likewise we implicitly need Integer when deriving things like Eq instances. The danger is that if the build system doesn't know about the dependency -on Integer, it'll compile some base module before GHC.Integer.Type, +on Integer, it'll compile some base module before GHC.Num.Integer, resulting in: - Failed to load interface for ‘GHC.Integer.Type’ - There are files missing in the ‘integer-gmp’ package, + Failed to load interface for ‘GHC.Num.Integer’ + There are files missing in the ‘ghc-bignum’ package, -Bottom line: we make GHC.Base depend on GHC.Integer; and everything +Bottom line: we make GHC.Base depend on GHC.Num.Integer; and everything else either depends on GHC.Base, or does not have NoImplicitPrelude (and hence depends on Prelude). +Note: this is only a problem with the make-based build system. Hadrian doesn't +seem to interleave compilation of modules from separate packages and respects +the dependency between `base` and `ghc-bignum`. + Note [Depend on GHC.Tuple] ~~~~~~~~~~~~~~~~~~~~~~~~~~ Similarly, tuple syntax (or ()) creates an implicit dependency on @@ -175,9 +177,6 @@ GHC.Tuple, so we use the same rule as for Integer --- see Note [Depend on GHC.Integer] --- to explain this to the build system. We make GHC.Base depend on GHC.Tuple, and everything else depends on GHC.Base or Prelude. -Note [Depend on GHC.Natural] -~~~~~~~~~~~~~~~~~~~~~~~~~~ -Similar to GHC.Integer. -} #if 0 |