The below header file produces an incorrect method type:

#include <stdarg.h>
int foo(const char* format, va_list va);

Specifically, the generated interface will look something like this:

public interface vastuff {
  public abstract int foo(java.nicl.types.Pointer<java.lang.Byte>, jextract.dump.usr_lib_llvm_3_7_lib_clang__3_7_1_include_stdarg$__va_list_tag[]);
}