[src/trunk]: src/usr.bin/xlint/lint1 lint: clean up the check for pointer con...

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/2fd7acf64939
branches:  trunk
changeset: 1020348:2fd7acf64939
user:      rillig <rillig%NetBSD.org@localhost>
date:      Fri Apr 09 19:52:59 2021 +0000

description:
lint: clean up the check for pointer conversions

No functional change.

diffstat:

 usr.bin/xlint/lint1/tree.c |  52 ++++++++++++++++++++-------------------------
 1 files changed, 23 insertions(+), 29 deletions(-)

diffs (121 lines):

diff -r 3fbd8be5426a -r 2fd7acf64939 usr.bin/xlint/lint1/tree.c
--- a/usr.bin/xlint/lint1/tree.c        Fri Apr 09 19:37:39 2021 +0000
+++ b/usr.bin/xlint/lint1/tree.c        Fri Apr 09 19:52:59 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: tree.c,v 1.272 2021/04/08 19:20:54 rillig Exp $        */
+/*     $NetBSD: tree.c,v 1.273 2021/04/09 19:52:59 rillig Exp $        */
 
 /*
  * Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,7 +37,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: tree.c,v 1.272 2021/04/08 19:20:54 rillig Exp $");
+__RCSID("$NetBSD: tree.c,v 1.273 2021/04/09 19:52:59 rillig Exp $");
 #endif
 
 #include <float.h>
@@ -74,7 +74,7 @@
                                         tnode_t *);
 static void    check_pointer_integer_conversion(op_t, tspec_t, type_t *,
                                                 tnode_t *);
-static void    check_pointer_conversion(op_t, tnode_t *, type_t *);
+static void    check_pointer_conversion(tnode_t *, type_t *);
 static tnode_t *build_struct_access(op_t, tnode_t *, tnode_t *);
 static tnode_t *build_prepost_incdec(op_t, tnode_t *);
 static tnode_t *build_real_imag(op_t, tnode_t *);
@@ -1849,8 +1849,8 @@
                /* a null pointer may be assigned to any pointer. */
        } else if (is_integer(nt) && nt != BOOL && ot == PTR) {
                check_pointer_integer_conversion(op, nt, tp, tn);
-       } else if (nt == PTR && ot == PTR) {
-               check_pointer_conversion(op, tn, tp);
+       } else if (nt == PTR && ot == PTR && op == CVT) {
+               check_pointer_conversion(tn, tp);
        }
 
        ntn = expr_zalloc_tnode();
@@ -2023,8 +2023,8 @@
 }
 
 static bool
-should_warn_about_pointer_cast(const type_t *ntp, tspec_t nst,
-                              const tnode_t *otn, tspec_t ost)
+should_warn_about_pointer_cast(const type_t *nstp, tspec_t nst,
+                              const type_t *ostp, tspec_t ost)
 {
        /*
         * Casting a pointer to 'struct S' to a pointer to another struct that
@@ -2032,14 +2032,12 @@
         * counter'.
         */
        if (nst == STRUCT && ost == STRUCT &&
-           ntp->t_subt->t_str->sou_first_member != NULL &&
-           ntp->t_subt->t_str->sou_first_member->s_type ==
-           otn->tn_type->t_subt)
+           nstp->t_str->sou_first_member != NULL &&
+           nstp->t_str->sou_first_member->s_type == ostp)
                return false;
 
-       if (nst == STRUCT || nst == UNION)
-               if (ntp->t_subt->t_str != otn->tn_type->t_subt->t_str)
-                       return true;
+       if ((nst == STRUCT || nst == UNION) && nstp->t_str != ostp->t_str)
+               return true;
 
        if (nst == CHAR || nst == UCHAR)
                return false;   /* for the sake of traditional C code */
@@ -2051,20 +2049,17 @@
  * Warn about questionable pointer conversions.
  */
 static void
-check_pointer_conversion(op_t op, tnode_t *tn, type_t *tp)
+check_pointer_conversion(tnode_t *tn, type_t *ntp)
 {
+       const type_t *nstp, *otp, *ostp;
        tspec_t nst, ost;
        const char *nts, *ots;
 
-       /*
-        * We got already an error (pointers of different types
-        * without a cast) or we will not get a warning.
-        */
-       if (op != CVT)
-               return;
-
-       nst = tp->t_subt->t_tspec;
-       ost = tn->tn_type->t_subt->t_tspec;
+       nstp = ntp->t_subt;
+       otp = tn->tn_type;
+       ostp = otp->t_subt;
+       nst = nstp->t_tspec;
+       ost = ostp->t_tspec;
 
        if (nst == VOID || ost == VOID) {
                if (sflag && (nst == FUNC || ost == FUNC)) {
@@ -2079,19 +2074,18 @@
                return;
        } else if (nst == FUNC || ost == FUNC) {
                /* converting '%s' to '%s' is questionable */
-               warning(229, type_name(tn->tn_type), type_name(tp));
+               warning(229, type_name(otp), type_name(ntp));
                return;
        }
 
-       if (hflag && alignment_in_bits(tp->t_subt) >
-                    alignment_in_bits(tn->tn_type->t_subt)) {
+       if (hflag && alignment_in_bits(nstp) > alignment_in_bits(ostp)) {
                /* converting '%s' to '%s' may cause alignment problem */
-               warning(135, type_name(tn->tn_type), type_name(tp));
+               warning(135, type_name(otp), type_name(ntp));
        }
 
-       if (cflag && should_warn_about_pointer_cast(tp, nst, tn, ost)) {
+       if (cflag && should_warn_about_pointer_cast(nstp, nst, ostp, ost)) {
                /* pointer cast from '%s' to '%s' may be troublesome */
-               warning(247, type_name(tn->tn_type), type_name(tp));
+               warning(247, type_name(otp), type_name(ntp));
        }
 }