Thread: CVS HEAD is broken by flex

I found CVS HEAD is broken and the following error is reported.
My environment is RHEL4 Update 2 x86_64 with gcc 3.4.4 and flex 2.5.33.

In file included from ../../../src/include/port.h:17,                from ../../../src/include/c.h:841,
from../../../src/include/postgres_fe.h:21,                from psqlscan.l:40:
 
/usr/include/netdb.h:560: error: syntax error before '[' token
make[3]: *** [psqlscan.o] Error 1
make[3]: *** Waiting for unfinished jobs....
make[2]: *** [all] Error 2
make[1]: *** [all] Error 2
make: *** [all] Error 2


The suspect is flex (or yy template file). It defines "__unused" to
be empty, but netdb.h uses "__unused" as a variable.
I found a similar case from google.
http://mailman.icsi.berkeley.edu/pipermail/xorp-cvs/2007-March/009928.html

[src/bin/psql/psqlscan.c]     9 #if defined(__FreeBSD__)    10 #include <sys/cdefs.h>    11 #else
->   12 #define __unused    13 #endif

[/usr/include/netdb.h]   552 struct gaicb   553 {   554   const char *ar_name;          /* Name to look up.  */   555
constchar *ar_service;       /* Service name.  */   556   const struct addrinfo *ar_request; /* Additional request
specification. */   557   struct addrinfo *ar_result;   /* Pointer to result.  */   558   /* The following are internal
elements. */   559   int __return;
 
->  560   int __unused[5];   561 };


Here is a brute fix for the problem, but it is probably improper.
What is better way to fix?

Index: src/include/port.h
===================================================================
--- src/include/port.h    (HEAD)
+++ src/include/port.h    (working copy)
@@ -13,6 +13,7 @@#ifndef PG_PORT_H#define PG_PORT_H
+#undef __unused#include <ctype.h>#include <netdb.h>#include <pwd.h>

Regards,
---
ITAGAKI Takahiro
NTT Open Source Software Center

ITAGAKI Takahiro <itagaki.takahiro@oss.ntt.co.jp> writes:
> The suspect is flex (or yy template file). It defines "__unused" to
> be empty, but netdb.h uses "__unused" as a variable.

Egad.  Shouldn't there be villagers breaking down the flex hackers'
front door with torches and pitchforks in hand?  Why is it our problem
to fix their stupidity?

> [src/bin/psql/psqlscan.c]
>       9 #if defined(__FreeBSD__)
>      10 #include <sys/cdefs.h>
>      11 #else
> ->   12 #define __unused
>      13 #endif

Surely lines 11 and 12 should simply go away.
        regards, tom lane