Publish portable Darling runtime patch snapshot and testing tools

tools/riot-objc-allocator-check.cpp

@@ -0,0 +1,22 @@
+#include <cstdlib>
+#include <cstdio>
+#include <new>
+#include <objc/runtime.h>
+static bool ready;
+static unsigned deletes;
+void* operator new(std::size_t n) { return std::malloc(n ? n : 1); }
+void* operator new[](std::size_t n) { return ::operator new(n); }
+void operator delete(void* p) noexcept {
+    if (p && !ready) { std::fputs("FAIL application delete used before main\n",stderr); std::abort(); }
+    if(p) ++deletes;
+    std::free(p);
+}
+void operator delete[](void* p) noexcept { ::operator delete(p); }
+int main() {
+    ready=true;
+    if(objc_getClassList(nullptr,0)<=0) return 1;
+    void* p=::operator new(64); ::operator delete(p);
+    if(deletes!=1) return 2;
+    std::puts("PASS Objective-C startup uses private allocation; app delete remains active");
+    return 0;
+}