[src/trunk]: src/usr.bin/xlint/lint1 lint: do not error out of a struct is in...

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

details:   https://anonhg.NetBSD.org/src/rev/8fd1607d2aff
branches:  trunk
changeset: 960884:8fd1607d2aff
user:      rillig <rillig%NetBSD.org@localhost>
date:      Thu Apr 01 14:20:30 2021 +0000

description:
lint: do not error out of a struct is initialized without braces

This allows to process lib/libc/gen/sysctl.c 1.38 from 2021-03-30, as
well as its precedessor 1.37, which had a workaround just for lint.

While unusual, C99 allows these.

diffstat:

 tests/usr.bin/xlint/lint1/d_c99_init.c   |   6 +++---
 tests/usr.bin/xlint/lint1/d_c99_init.exp |   1 -
 usr.bin/xlint/lint1/init.c               |  18 +++++++++---------
 3 files changed, 12 insertions(+), 13 deletions(-)

diffs (94 lines):

diff -r 4e0af792322e -r 8fd1607d2aff tests/usr.bin/xlint/lint1/d_c99_init.c
--- a/tests/usr.bin/xlint/lint1/d_c99_init.c    Thu Apr 01 10:35:24 2021 +0000
+++ b/tests/usr.bin/xlint/lint1/d_c99_init.c    Thu Apr 01 14:20:30 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: d_c99_init.c,v 1.29 2021/03/30 19:45:04 rillig Exp $   */
+/*     $NetBSD: d_c99_init.c,v 1.30 2021/04/01 14:20:30 rillig Exp $   */
 # 3 "d_c99_init.c"
 
 /*
@@ -275,8 +275,8 @@
 struct {
        int a[3], b;
 } c99_6_7_8_p28_example5[] = {
-       { 1 },
-       2,                      /* XXX *//* expect: cannot initialize */
+       { 1 },          /* just parsed, not checked in detail */
+       2,              /* just parsed, not checked in detail */
 };
 
 short c99_6_7_8_p29_example6a[4][3][2] = {
diff -r 4e0af792322e -r 8fd1607d2aff tests/usr.bin/xlint/lint1/d_c99_init.exp
--- a/tests/usr.bin/xlint/lint1/d_c99_init.exp  Thu Apr 01 10:35:24 2021 +0000
+++ b/tests/usr.bin/xlint/lint1/d_c99_init.exp  Thu Apr 01 14:20:30 2021 +0000
@@ -9,7 +9,6 @@
 d_c99_init.c(230): error: too many struct/union initializers [172]
 d_c99_init.c(236): warning: illegal combination of integer (char) and pointer (pointer to char) [183]
 d_c99_init.c(240): warning: illegal combination of integer (char) and pointer (pointer to char) [183]
-d_c99_init.c(279): error: cannot initialize 'struct <unnamed>' from 'int' [185]
 d_c99_init.c(321): error: duplicate case in switch: 0 [199]
 d_c99_init.c(330): error: type 'struct point' does not have member 'r' [101]
 d_c99_init.c(337): error: type 'struct point' does not have member 'r' [101]
diff -r 4e0af792322e -r 8fd1607d2aff usr.bin/xlint/lint1/init.c
--- a/usr.bin/xlint/lint1/init.c        Thu Apr 01 10:35:24 2021 +0000
+++ b/usr.bin/xlint/lint1/init.c        Thu Apr 01 14:20:30 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: init.c,v 1.184 2021/03/30 20:23:30 rillig Exp $        */
+/*     $NetBSD: init.c,v 1.185 2021/04/01 14:20:30 rillig Exp $        */
 
 /*
  * Copyright (c) 1994, 1995 Jochen Pohl
@@ -38,7 +38,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: init.c,v 1.184 2021/03/30 20:23:30 rillig Exp $");
+__RCSID("$NetBSD: init.c,v 1.185 2021/04/01 14:20:30 rillig Exp $");
 #endif
 
 #include <stdlib.h>
@@ -126,7 +126,7 @@
        size_t          bl_array_next_subscript;
        bool            bl_array_of_unknown_size: 1;
        bool            bl_scalar_done: 1;      /* for scalars */
-       bool            bl_omitted_braces: 1;   /* skip further checks */
+       bool            bl_confused: 1;         /* skip further checks */
        struct designation bl_designation;      /* .member[123].member */
        struct brace_level *bl_enclosing;
 };
@@ -608,8 +608,7 @@
 brace_level_sub_type_array(const struct brace_level *bl)
 {
 
-       if (!bl->bl_type->t_incomplete_array &&
-           !bl->bl_omitted_braces &&
+       if (!bl->bl_confused && !bl->bl_type->t_incomplete_array &&
            bl->bl_array_next_subscript >= (size_t)bl->bl_type->t_dim) {
                /* too many array initializers, expected %d */
                error(173, bl->bl_type->t_dim);
@@ -939,7 +938,7 @@
                return;
 
        bl = in->in_brace_level;
-       if (bl != NULL && bl->bl_omitted_braces)
+       if (bl != NULL && bl->bl_confused)
                return;
 
        debug_enter();
@@ -967,12 +966,13 @@
         * Hack to accept initializations with omitted braces, see
         * c99_6_7_8_p28_example5 in test d_c99_init.c.  Since both GCC and
         * Clang already warn about this at level -Wall, there is no point
-        * in letting lint check this again.
+        * in repeating the same check in lint.  If needed, support for these
+        * edge cases could be added, but that would increase the complexity.
         */
        if (is_scalar(tn->tn_type->t_tspec) &&
-           tp->t_tspec == ARRAY &&
+           (tp->t_tspec == ARRAY || is_struct_or_union(tp->t_tspec)) &&
            bl != NULL) {
-               bl->bl_omitted_braces = true;
+               bl->bl_confused = true;
                goto done;
        }