Fix unregisterised buildwip/gc/nonmoving-concurrent

This required some fiddling around with the location of forward
declarations since the C sources generated by GHC's C backend only
includes Stg.h.

2 files changed, 25 insertions, 4 deletions

diff --git a/includes/rts/NonMoving.h b/includes/rts/NonMoving.h
index f64769e8a9..314c582a1e 100644
--- a/includes/rts/NonMoving.h
+++ b/includes/rts/NonMoving.h
@@ -13,10 +13,31 @@
 
 #pragma once
 
+// Forward declaration for Stg.h
+struct StgClosure_;
+struct StgThunk_;
+struct Capability_;
+
 /* This is called by the code generator */
 extern DLL_IMPORT_RTS
-void updateRemembSetPushClosure_(StgRegTable *reg, StgClosure *p);
+void updateRemembSetPushClosure_(StgRegTable *reg, struct StgClosure_ *p);
+
+extern DLL_IMPORT_RTS
+void updateRemembSetPushThunk_(StgRegTable *reg, struct StgThunk_ *p);
+
+// Forward declaration for unregisterised backend.
+EF_(stg_copyArray_barrier);
 
-void updateRemembSetPushClosure(Capability *cap, StgClosure *p);
+// Note that RTS code should not condition on this directly by rather
+// use the IF_NONMOVING_WRITE_BARRIER_ENABLED macro to ensure that
+// the barrier is eliminated in the non-threaded RTS.
+extern StgWord DLL_IMPORT_DATA_VAR(nonmoving_write_barrier_enabled);
 
-void updateRemembSetPushThunk_(StgRegTable *reg, StgThunk *p);
+// A similar macro is defined in includes/Cmm.h for C-- code.
+#if defined(THREADED_RTS)
+#define IF_NONMOVING_WRITE_BARRIER_ENABLED \
+    if (RTS_UNLIKELY(nonmoving_write_barrier_enabled))
+#else
+#define IF_NONMOVING_WRITE_BARRIER_ENABLED \
+    if (0)
+#endif
diff --git a/includes/rts/storage/Closures.h b/includes/rts/storage/Closures.h
index 6088fc8a10..b2b5eda407 100644
--- a/includes/rts/storage/Closures.h
+++ b/includes/rts/storage/Closures.h
@@ -94,7 +94,7 @@ typedef struct StgClosure_ {
     struct StgClosure_ *payload[];
 } *StgClosurePtr; // StgClosure defined in rts/Types.h
 
-typedef struct {
+typedef struct StgThunk_ {
     StgThunkHeader  header;
     struct StgClosure_ *payload[];
 } StgThunk;