fixes #1593

tests/ccgbugs/tcvarargs.nim

@@ -0,0 +1,34 @@
+discard """
+  output: '''17
+17
+17
+17
+17
+17
+'''
+"""
+
+# bug #1593
+
+{.emit: """
+#include <stdarg.h>
+
+void foo(int n, ...) {
+  NI64 k;
+  int i;
+  va_list argp;
+  va_start(argp, n);
+  for (i = 1; i <= n; i++) {
+    k = va_arg(argp, NI64);
+    printf("%lld\n", (long long)k);
+  }
+  va_end(argp);
+}
+""".}
+
+proc foo(x: cint) {.importc, varargs, nodecl.}
+
+proc main() =
+  const k = 17'i64
+  foo(6, k, k, k, k, k, k)
+main()