xref: /src/tests/usr.bin/xlint/lint1/msg_135.c

/*	$NetBSD: msg_135.c,v 1.10 2022/06/11 11:52:13 rillig Exp $	*/
# 3 "msg_135.c"

// Test for message: converting '%s' to '%s' may cause alignment problem [135]

/* lint1-extra-flags: -h */

void sink(const void *);

unsigned
read_uint(const unsigned short **pp)
{
	unsigned val;

	/* expect+1: warning: converting 'pointer to const unsigned short' to 'pointer to const unsigned int' may cause alignment problem [135] */
	val = *(const unsigned *)(*pp);
	pp += sizeof(unsigned);
	return val;
}

/* expect+1: warning: struct 'incomplete' never defined [233] */
struct incomplete;

struct complete {
    int member;
};

/*
 * These types of conversions are typically seen in OpenSSL, when converting
 * from the publicly visible, incomplete 'struct lhash_st' to a private
 * implementation type such as 'struct lhash_st_OPENSSL_STRING'.
 *
 * Before tree.c 1.277 from 2021-04-17, lint warned about this, even though
 * there was not enough evidence that there really was an alignment problem,
 * resulting in many false positives.
 *
 * See openssl/lhash.h.
 */
void
pointer_to_structs(struct incomplete *incomplete)
{
	struct complete *complete;

	complete = (struct complete *)incomplete;
	sink(complete);
}

/*
 * Before tree.c 1.316 from 2021-07-15, lint warned about pointer casts from
 * unsigned char or plain char to another type.  These casts often occur in
 * traditional code that does not use void pointers, even 30 years after C90
 * introduced 'void'.
 */
void
unsigned_char_to_unsigned_type(unsigned char *ucp)
{
	unsigned short *usp;

	usp = (unsigned short *)ucp;
	sink(usp);
}

/*
 * Before tree.c 1.316 from 2021-07-15, lint warned about pointer casts from
 * unsigned char or plain char to another type.  These casts often occur in
 * traditional code that does not use void pointers, even 30 years after C90
 * introduced 'void'.
 */
void
plain_char_to_unsigned_type(char *cp)
{
	unsigned short *usp;

	usp = (unsigned short *)cp;
	sink(usp);
}