implement most of preprocessor

  - concatenation (##)
  - builtin macros (__FILE__ etc)
  - fails in some edge cases, and code needs cleanup
  - add embedded system include files (stddef.h, stdarg.h for now)
  - can handle stdio.h now

1 files changed, 1 insertions, 1 deletions

diff --git a/test/hello.c b/test/hello.c
index 9d21323..e27be8d 100644
--- a/test/hello.c
+++ b/test/hello.c
@@ -1,4 +1,4 @@
-int printf(char *, ...);
+#include <stdio.h>
 int main(int argc, char **argv) {
    printf("hello world\n");
 }