This patch adds a new third-party library that implements an ELF dynamic linker.

third_party/crazy_linker/crazy_linker/tests/foo_with_static_constructor.cpp

Index: third_party/crazy_linker/crazy_linker/tests/foo_with_static_constructor.cpp
diff --git a/third_party/crazy_linker/crazy_linker/tests/foo_with_static_constructor.cpp b/third_party/crazy_linker/crazy_linker/tests/foo_with_static_constructor.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..50ed01601a3d87a0005ab540b7cbba9d62ce6f2f
--- /dev/null
+++ b/third_party/crazy_linker/crazy_linker/tests/foo_with_static_constructor.cpp
@@ -0,0 +1,39 @@
+// This source file must contain a static destructor to check that
+// the crazy linker can resolve weak symbols from the C library,
+// like __aeabi_atexit(), which are not normally returned by
+// a call to dlsym().
+
+#include <stdlib.h>
+
+extern "C" void __aeabi_atexit(void*);
+
+class A {
+ public:
+  A() {
+    x_ = rand();
+    const char* env = getenv("TEST_VAR");
+    if (!env || strcmp(env, "INIT"))
+      putenv("TEST_VAR=LOAD_ERROR");
+    else
+      putenv("TEST_VAR=LOADED");
+  }
+
+  ~A() {
+    const char* env = getenv("TEST_VAR");
+    if (!env || strcmp(env, "LOADED"))
+      putenv("TEST_VAR=UNLOAD_ERROR");
+    else
+      putenv("TEST_VAR=UNLOADED");
+  }
+
+  int Get() const { return x_; }
+
+ private:
+  int x_;
+};
+
+A s_a;
+
+extern "C" int Foo() {
+  return s_a.Get();
+}