3rdparty: Avoid the need for -fpermissive since clang doesn't like it.

I'll try to get some of this upstreamed.

3rdparty/linenoise/utf8.c

@@ -202,7 +202,7 @@ static int cmp_range(const void *key, const void *cm)
 static int utf8_in_range(const struct utf8range *range, int num, int ch)
 {
     const struct utf8range *r =
-        bsearch(&ch, range, num, sizeof(*range), cmp_range);
+        (const struct utf8range *)bsearch(&ch, range, num, sizeof(*range), cmp_range);
 
     if (r) {
         return 1;

3rdparty/lsqlite3/lsqlite3.c

@@ -175,7 +175,7 @@ static void vm_push_column(lua_State *L, sqlite3_stmt *vm, int idx) {
             lua_pushlstring(L, (const char*)sqlite3_column_text(vm, idx), sqlite3_column_bytes(vm, idx));
             break;
         case SQLITE_BLOB:
-            lua_pushlstring(L, sqlite3_column_blob(vm, idx), sqlite3_column_bytes(vm, idx));
+            lua_pushlstring(L, (const char*)sqlite3_column_blob(vm, idx), sqlite3_column_bytes(vm, idx));
             break;
         case SQLITE_NULL:
             lua_pushnil(L);
@@ -667,7 +667,7 @@ static int cleanupdb(lua_State *L, sdb *db) {
     top = lua_gettop(L);
     lua_pushnil(L);
     while (lua_next(L, -2)) {
-        sdb_vm *svm = lua_touserdata(L, -2); /* key: vm; val: sql text */
+        sdb_vm *svm = (sdb_vm*)lua_touserdata(L, -2); /* key: vm; val: sql text */
         cleanupvm(L, svm);
 
         lua_settop(L, top);
@@ -961,7 +961,7 @@ static void db_push_value(lua_State *L, sqlite3_value *value) {
             break;
 
         case SQLITE_BLOB:
-            lua_pushlstring(L, sqlite3_value_blob(value), sqlite3_value_bytes(value));
+            lua_pushlstring(L, (const char*)sqlite3_value_blob(value), sqlite3_value_bytes(value));
             break;
 
         case SQLITE_NULL:
@@ -1179,8 +1179,8 @@ static int collwrapper(scc *co,int l1,const void *p1,
     int res=0;
     lua_State *L=co->L;
     lua_rawgeti(L,LUA_REGISTRYINDEX,co->ref);
-    lua_pushlstring(L,p1,l1);
-    lua_pushlstring(L,p2,l2);
+    lua_pushlstring(L,(const char*)p1,l1);
+    lua_pushlstring(L,(const char*)p2,l2);
     if (lua_pcall(L,2,1,0)==0) res=(int)lua_tonumber(L,-1);
     lua_pop(L,1);
     return res;
@@ -2001,7 +2001,7 @@ static int db_close_vm(lua_State *L) {
     /* close all used handles */
     lua_pushnil(L);
     while (lua_next(L, -2)) {
-        sdb_vm *svm = lua_touserdata(L, -2); /* key: vm; val: sql text */
+        sdb_vm *svm = (sdb_vm*)lua_touserdata(L, -2); /* key: vm; val: sql text */
 
         if ((!temp || svm->temp) && svm->vm)
         {
@@ -2112,7 +2112,7 @@ static int lsqlite_open_ptr(lua_State *L) {
     int rc;
 
     luaL_checktype(L, 1, LUA_TLIGHTUSERDATA);
-    db_ptr = lua_touserdata(L, 1);
+    db_ptr = (sqlite3*)lua_touserdata(L, 1);
     /* This is the only API function that runs sqlite3SafetyCheck regardless of
      * SQLITE_ENABLE_API_ARMOR and does almost nothing (without an SQL
      * statement) */

3rdparty/lua-zlib/lua_zlib.c

@@ -353,8 +353,8 @@ static int lz_checksum(lua_State *L) {
 }
 
 static int lz_checksum_new(lua_State *L, checksum_t checksum, checksum_combine_t combine) {
-    lua_pushlightuserdata(L, checksum);
-    lua_pushlightuserdata(L, combine);
+    lua_pushlightuserdata(L, (void *)checksum);
+    lua_pushlightuserdata(L, (void *)combine);
     lua_pushnumber(L, checksum(0L, Z_NULL, 0));
     lua_pushnumber(L, 0);
     lua_pushcclosure(L, lz_checksum, 4);

3rdparty/luafilesystem/src/lfs.c

@@ -288,7 +288,7 @@ static int get_dir(lua_State * L)
   size_t size = LFS_MAXPATHLEN; /* initial buffer size */
   int result;
   while (1) {
-    char *path2 = realloc(path, size);
+    char *path2 = (char *)realloc(path, size);
     if (!path2) {               /* failed to allocate */
       result = pusherror(L, "get_dir realloc() failed");
       break;
@@ -1078,7 +1078,7 @@ static int push_link_target(lua_State * L)
   int tsize, size = 256;        /* size = initial buffer capacity */
   int ok = 0;
   while (!ok) {
-    char *target2 = realloc(target, size);
+    char *target2 = (char *)realloc(target, size);
     if (!target2) {             /* failed to allocate */
       break;
     }

scripts/src/3rdparty.lua

@@ -936,9 +936,8 @@ project "lualibs"
 	}
 
 	configuration { "gmake or ninja" }
-		buildoptions { -- Lua SQLite3, Lua filesystem and Lua zlib don't cast pointers* explicitly
-			"-Wno-error",
-			"-fpermissive",
+		buildoptions {
+			"-Wno-error=unused-variable",
 		}
 
 	configuration { "vs*" }
@@ -1680,9 +1679,9 @@ project "linenoise"
 	}
 
 	configuration { "gmake or ninja" }
-		buildoptions { -- implicit pointer conversions
-			"-Wno-error",
-			"-fpermissive",
+		buildoptions {
+			"-Wno-error=unused-variable",
+			"-Wno-error=implicit-fallthrough",
 		}
 
 	configuration { "vs*" }