[domain] Don't add NULL runtime to runtimes list (mono/mono#18260)

Also when iterating over the runtimes, actually look at the current element,
not the first element.

Also mention the unsupported runtime version in the warning message when it is
passed to mono_init_internal.

Fixes https://github.com/mono/mono/issues/17916

Commit migrated from https://github.com/mono/mono/commit/ffdffa54f2494cfdf390fabfc76e353fbe59405a

diff --git a/src/mono/mono/metadata/domain.c b/src/mono/mono/metadata/domain.c
index 47056f6..061ba22 100644 (file)
--- a/src/mono/mono/metadata/domain.c
+++ b/src/mono/mono/metadata/domain.c
@@ -590,20 +590,27 @@ mono_init_internal (const char *filename, const char *exe_filename, const char *
                mono_fixup_exe_image (exe_image);
 #endif
        } else if (runtime_version != NULL) {
-               runtimes = g_slist_prepend (runtimes, (gpointer)get_runtime_by_version (runtime_version));
+               const MonoRuntimeInfo* rt = get_runtime_by_version (runtime_version);
+               if (rt != NULL)
+                       runtimes = g_slist_prepend (runtimes, (gpointer)rt);
        }
 
        if (runtimes == NULL) {
                const MonoRuntimeInfo *default_runtime = get_runtime_by_version (DEFAULT_RUNTIME_VERSION);
+               g_assert (default_runtime);
                runtimes = g_slist_prepend (runtimes, (gpointer)default_runtime);
-               g_print ("WARNING: The runtime version supported by this application is unavailable.\n");
+               if (runtime_version != NULL)
+                       g_print ("WARNING: The requested runtime version \"%s\" is unavailable.\n", runtime_version);
+               else
+                       g_print ("WARNING: The runtime version supported by this application is unavailable.\n");
                g_print ("Using default runtime: %s\n", default_runtime->runtime_version); 
        }
 
        /* The selected runtime will be the first one for which there is a mscrolib.dll */
        GSList *tmp = runtimes;
        while (tmp != NULL) {
-               current_runtime = (MonoRuntimeInfo*)runtimes->data;
+               current_runtime = (MonoRuntimeInfo*)tmp->data;
+               g_assert (current_runtime);
                ass = mono_assembly_load_corlib (current_runtime, &status);
                if (status != MONO_IMAGE_OK && status != MONO_IMAGE_ERROR_ERRNO)
                        break;