driver: ensure static archives are picked when linking static .wasm modules

This commit ensures static archives are picked when linking .wasm
modules which are supposed to be fully static, even when ghc may be
invoked with -dynamic, see added comment for explanation.

(cherry picked from commit 47baa904)

compiler/GHC/Linker/Static.hs

@@ -77,7 +77,17 @@ linkBinary' staticLink logger tmpfs dflags unit_env o_files dep_units = do
         arch_os   = platformArchOS platform
         output_fn = exeFileName arch_os staticLink (outputFile_ dflags)
         namever   = ghcNameVersion dflags
-        ways_     = ways dflags
+        -- For the wasm target, when ghc is invoked with -dynamic,
+        -- when linking the final .wasm binary we must still ensure
+        -- the static archives are selected. Otherwise wasm-ld would
+        -- fail to find and link the .so library dependencies. wasm-ld
+        -- can link PIC objects into static .wasm binaries fine, so we
+        -- only adjust the ways in the final linking step, and only
+        -- when linking .wasm binary (which is supposed to be fully
+        -- static), not when linking .so shared libraries.
+        ways_
+          | ArchWasm32 <- platformArch platform = removeWay WayDyn $ targetWays_ dflags
+          | otherwise = ways dflags
 
     full_output_fn <- if isAbsolute output_fn
                       then return output_fn