Replace pragma to disable warnings with a less intrusive method

include/internal/generic/fmpi_futhark_generic.h

@@ -48,28 +48,17 @@ struct fmpi_futhark_ctx;
 #define FMPI_FUTHARK_ARRAY_ENTRY_LIST(D) \
     CPL_MAP_FIXED(FMPI_PRIV_FUTHARK_ARRAY_ENTRY, CPL_COMMA, (D), FMPI_FUTHARK_TYPES)
 
-#if defined(__GNUC__) || defined(__GNUG__)
-    _Pragma("GCC diagnostic ignored \"-Wunused-parameter\"")
-    _Pragma("GCC diagnostic push")
-#elif defined(__clang__)
-    _Pragma("clang diagnostic ignored \"-Wunused-parameter\"")
-    _Pragma("clang diagnostic push")
-#endif
-
+// In a comma separeted list of expressions contained in a pair of parentheses
+// only the last one is returned, allowing to silence warnings about unused
+// parameters by putting them first.
 #define FMPI_FUTHARK_NEW_1(T, ctx, array, x, y, z) \
-    futhark_new_##T##_1d(ctx, array, (int64_t)(x));
+    ((void)(y), (void)(z), futhark_new_##T##_1d(ctx, array, (int64_t)(x)))
 
 #define FMPI_FUTHARK_NEW_2(T, ctx, array, x, y, z) \
-    futhark_new_##T##_2d(ctx, array, (int64_t)(x), (int64_t)(y));
-
-#if defined(__GNUC__) || defined(__GNUG__)
-    _Pragma("GCC diagnostic push")
-#elif defined(__clang__)
-    _Pragma("clang diagnostic push")
-#endif
+    ((void)(z), futhark_new_##T##_2d(ctx, array, (int64_t)(x), (int64_t)(y)))
 
 #define FMPI_FUTHARK_NEW_3(T, ctx, array, x, y, z) \
-    futhark_new_##T##_3d(ctx, array, (int64_t)(x), (int64_t)(y), (int64_t)(z));
+    futhark_new_##T##_3d(ctx, array, (int64_t)(x), (int64_t)(y), (int64_t)(z))
 
 #define FMPI_FUTHARK_DECLARATION(D, T) \
 void * fmpi_futhark_new_##D##d_##T( \