added better support for structs for extern functions, added a flag to disable list folding and made extern functions automaticly have priority 1

extra_tests/c_extern_structs.c

@@ -0,0 +1,42 @@
+#include <stdint.h>
+#include <time.h>
+
+typedef struct {
+    int64_t a;
+    int64_t b;
+} Pair;
+
+typedef struct {
+    int64_t a;
+    int64_t b;
+    int64_t c;
+} Big;
+
+long long pair_sum(Pair p) {
+    return (long long)(p.a + p.b);
+}
+
+Pair make_pair(long long seed) {
+    Pair out;
+    out.a = seed;
+    out.b = seed + 10;
+    return out;
+}
+
+Big make_big(long long seed) {
+    Big out;
+    out.a = seed;
+    out.b = seed + 1;
+    out.c = seed + 2;
+    return out;
+}
+
+long long big_sum(Big b) {
+    return b.a + b.b + b.c;
+}
+
+long long pair_after_six(long long a, long long b, long long c,
+                         long long d, long long e, long long f,
+                         Pair p) {
+    return a + b + c + d + e + f + p.a + p.b;
+}