Fix a few GCC warnings

GCC 8 now generates warnings for incompatible function pointer casts
[-Werror=cast-function-type]. Apparently there are a few of those in rts
code, which makes `./validate` unhappy (since we compile with `-Werror`)

This commit tries to fix these issues by changing the functions to have
the correct type (and, if necessary, moving the casts into those
functions).

For instance, hash/comparison function are declared (`Hash.h`) to take
`StgWord` but we want to use `StgWord64[2]` in `StaticPtrTable.c`.
Instead of casting the function pointers, we can cast the `StgWord`
parameter to `StgWord*`. I think this should be ok since `StgWord`
should be the same size as a pointer.

Signed-off-by: Michal Terepeta <michal.terepeta@gmail.com>

Test Plan: ./validate

Reviewers: bgamari, erikd, simonmar

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4673

1 files changed, 1 insertions, 1 deletions

diff --git a/rts/Hash.h b/rts/Hash.h
index 1dde314d0e..be388fb62f 100644
--- a/rts/Hash.h
+++ b/rts/Hash.h
@@ -56,7 +56,7 @@ typedef int HashFunction(const HashTable *table, StgWord key);
 typedef int CompareFunction(StgWord key1, StgWord key2);
 HashTable * allocHashTable_(HashFunction *hash, CompareFunction *compare);
 int hashWord(const HashTable *table, StgWord key);
-int hashStr(const HashTable *table, char *key);
+int hashStr(const HashTable *table, StgWord key);
 
 /* Freeing hash tables
  */