[src/trunk]: src/usr.bin/xlint/lint1 lint: document i_brace, add comments, re...

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

details:   https://anonhg.NetBSD.org/src/rev/c5d1415ca28c
branches:  trunk
changeset: 980888:c5d1415ca28c
user:      rillig <rillig%NetBSD.org@localhost>
date:      Sun Feb 21 13:13:14 2021 +0000

description:
lint: document i_brace, add comments, rename initstack_string

No functional change outside debug mode.

diffstat:

 usr.bin/xlint/lint1/init.c |  35 +++++++++++++++++++++++------------
 1 files changed, 23 insertions(+), 12 deletions(-)

diffs (104 lines):

diff -r 4cbd0e6f0798 -r c5d1415ca28c usr.bin/xlint/lint1/init.c
--- a/usr.bin/xlint/lint1/init.c        Sun Feb 21 13:10:57 2021 +0000
+++ b/usr.bin/xlint/lint1/init.c        Sun Feb 21 13:13:14 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: init.c,v 1.81 2021/02/21 11:23:33 rillig Exp $ */
+/*     $NetBSD: init.c,v 1.82 2021/02/21 13:13:14 rillig Exp $ */
 
 /*
  * Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,7 +37,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: init.c,v 1.81 2021/02/21 11:23:33 rillig Exp $");
+__RCSID("$NetBSD: init.c,v 1.82 2021/02/21 13:13:14 rillig Exp $");
 #endif
 
 #include <stdlib.h>
@@ -68,8 +68,18 @@
        type_t  *i_type;                /* type of initialisation */
        type_t  *i_subt;                /* type of next level */
 
-       /* need '}' for pop; XXX: explain this */
+       /*
+        * This level of the initializer requires a '}' to be completed.
+        *
+        * Multidimensional arrays do not need a closing brace to complete
+        * an inner array; for example, { 1, 2, 3, 4 } is a valid initializer
+        * for int arr[2][2].
+        *
+        * TODO: Do structs containing structs need a closing brace?
+        * TODO: Do arrays of structs need a closing brace after each struct?
+        */
        bool i_brace: 1;
+
        bool i_array_of_unknown_size: 1;
        bool i_seen_named_member: 1;
 
@@ -133,7 +143,7 @@
 namlist_t      *namedmem = NULL;
 
 
-static bool    initstack_string(tnode_t *);
+static bool    init_array_using_string(tnode_t *);
 
 #ifndef DEBUG
 #define debug_printf(fmt, ...) do { } while (false)
@@ -759,24 +769,22 @@
         */
        if ((sclass == AUTO || sclass == REG) &&
            initsym->s_type->t_tspec != ARRAY && initstk->i_enclosing == NULL) {
+               debug_step("handing over to ASSIGN");
                ln = new_name_node(initsym, 0);
                ln->tn_type = tduptyp(ln->tn_type);
                ln->tn_type->t_const = false;
                tn = build(ASSIGN, ln, tn);
                expr(tn, false, false, false, false);
-               debug_initstack();
+               /* XXX: why not clean up the initstack here already? */
                debug_leave();
                return;
        }
 
-       /*
-        * Remove all entries which cannot be used for further initializers
-        * and do not require a closing brace.
-        */
        initstack_pop_nobrace();
 
-       /* Initialisations by strings are done in initstack_string(). */
-       if (initstack_string(tn)) {
+       if (init_array_using_string(tn)) {
+               debug_step("after initializing the string:");
+               /* XXX: why not clean up the initstack here already? */
                debug_initstack();
                debug_leave();
                return;
@@ -852,8 +860,9 @@
 }
 
 
+/* Initialize a character array or wchar_t array with a string literal. */
 static bool
-initstack_string(tnode_t *tn)
+init_array_using_string(tnode_t *tn)
 {
        tspec_t t;
        initstack_element *istk;
@@ -882,6 +891,7 @@
                        debug_leave();
                        return false;
                }
+               /* XXX: duplicate code, see below */
                /* Put the array at top of stack */
                initstack_push();
                istk = initstk;
@@ -894,6 +904,7 @@
                        debug_leave();
                        return false;
                }
+               /* XXX: duplicate code, see above */
                /*
                 * If the array is already partly initialized, we are
                 * wrong here.