Properly link flecs library

engine/libs/flecs/test/custom_builds/cpp/app/include/app.h

@@ -0,0 +1,16 @@
+#ifndef APP_H
+#define APP_H
+
+/* This generated file contains includes for project dependencies */
+#include "app/bake_config.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+

engine/libs/flecs/test/custom_builds/cpp/app/include/app/bake_config.h

@@ -0,0 +1,24 @@
+/*
+                                   )
+                                  (.)
+                                  .|.
+                                  | |
+                              _.--| |--._
+                           .-';  ;`-'& ; `&.
+                          \   &  ;    &   &_/
+                           |"""---...---"""|
+                           \ | | | | | | | /
+                            `---.|.|.|.---'
+
+ * This file is generated by bake.lang.c for your convenience. Headers of
+ * dependencies will automatically show up in this file. Include bake_config.h
+ * in your main project file. Do not edit! */
+
+#ifndef APP_BAKE_CONFIG_H
+#define APP_BAKE_CONFIG_H
+
+/* Headers of public dependencies */
+#include "../../deps/flecs.h"
+
+#endif
+

engine/libs/flecs/test/custom_builds/cpp/app/project.json

@@ -0,0 +1,15 @@
+{
+    "id": "app",
+    "type": "application",
+    "value": {
+        "use": [
+            "flecs"
+        ],
+        "public": false,
+        "standalone": true,
+        "language": "c++"
+    },
+    "lang.cpp": {
+        "defines": ["FLECS_CUSTOM_BUILD", "FLECS_CPP", "FLECS_APP"]
+    }
+}

engine/libs/flecs/test/custom_builds/cpp/app/src/main.cpp

@@ -0,0 +1,11 @@
+#include <app.h>
+
+int main(int, char *[]) {
+    flecs::world ecs;
+
+    ecs.system().iter([](flecs::iter& it) {
+        it.world().quit();
+    });
+    
+    return ecs.app().run();
+}