Add a test that tests the module and symbol resolution with dlopen.

test cases/common/125 shared module/meson.build

@@ -1,4 +1,8 @@
 project('shared module', 'c')
 
-shared_module('mymodule', 'module.c')
+dl = meson.get_compiler('c').find_library('dl', required : false)
+l = shared_library('runtime', 'runtime.c')
+m = shared_module('mymodule', 'module.c')
+e = executable('prog', 'prog.c', link_with : l, dependencies : dl)
+test('import test', e, args : [m.full_path()])
 

test cases/common/125 shared module/module.c

@@ -11,12 +11,12 @@
 
 /*
  * Shared modules often have references to symbols that are not defined
- * at link time, but which will be provided by the executable that
+ * at link time, but which will be provided from deps of the executable that
  * dlopens it. We need to make sure that this works, i.e. that we do
  * not pass -Wl,--no-undefined when linking modules.
  */
-int nonexisting_function();
+int func_from_language_runtime();
 
 int DLL_PUBLIC func() {
-    return nonexisting_function();
+    return func_from_language_runtime();
 }

test cases/common/125 shared module/prog.c

@@ -0,0 +1,38 @@
+#ifdef _WIN32
+// FIXME: add implementation using Winapi functions for dlopen.
+
+int main(int argc, char **argv) {
+    return 0;
+}
+
+#else
+
+#include<dlfcn.h>
+#include<assert.h>
+#include<stdio.h>
+
+int func();
+int func_from_language_runtime();
+
+int main(int argc, char **argv) {
+    void *dl;
+    int (*importedfunc)();
+    int success;
+    char *error;
+
+    dlerror();
+    dl = dlopen(argv[1], RTLD_LAZY);
+    error = dlerror();
+    if(error) {
+        printf("Could not open %s: %s\n", argv[1], error);
+        return 1;
+    }
+    importedfunc = (int (*)()) dlsym(dl, "func");
+    assert(importedfunc);
+    assert(importedfunc != func_from_language_runtime);
+    success = (*importedfunc)() == func_from_language_runtime();
+    dlclose(dl);
+    return !success;
+}
+
+#endif

test cases/common/125 shared module/runtime.c

@@ -0,0 +1,19 @@
+#if defined _WIN32 || defined __CYGWIN__
+  #define DLL_PUBLIC __declspec(dllexport)
+#else
+  #if defined __GNUC__
+    #define DLL_PUBLIC __attribute__ ((visibility("default")))
+  #else
+    #pragma message ("Compiler does not support symbol visibility.")
+    #define DLL_PUBLIC
+  #endif
+#endif
+
+/*
+ * This file pretends to be a language runtime that supports extension
+ * modules.
+ */
+
+int func_from_language_runtime() {
+    return 86;
+}