[src/trunk]: src/usr.bin/xlint/lint1 lint: clean up debug logging in initstac...

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

details:   https://anonhg.NetBSD.org/src/rev/a05b77548ee1
branches:  trunk
changeset: 952921:a05b77548ee1
user:      rillig <rillig%NetBSD.org@localhost>
date:      Sun Feb 21 10:03:35 2021 +0000

description:
lint: clean up debug logging in initstack_pop_item

The debug logging contained much redundant information and was
misleading in a few places.  For example, "pop" did not actually pop an
item, plus there are several things that could be popped, so that didn't
help either.

Sprinkle some comments in places where the code needs to become clearer.

No functional change outside debug mode.  The condition
'istk->i_remaining >= 0' was redundant due to the assertion directly
above it.

diffstat:

 usr.bin/xlint/lint1/init.c |  39 ++++++++++++++++++++-------------------
 1 files changed, 20 insertions(+), 19 deletions(-)

diffs (109 lines):

diff -r d9f8b9b77386 -r a05b77548ee1 usr.bin/xlint/lint1/init.c
--- a/usr.bin/xlint/lint1/init.c        Sun Feb 21 09:24:32 2021 +0000
+++ b/usr.bin/xlint/lint1/init.c        Sun Feb 21 10:03:35 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: init.c,v 1.79 2021/02/21 09:24:32 rillig Exp $ */
+/*     $NetBSD: init.c,v 1.80 2021/02/21 10:03:35 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 1.79 2021/02/21 09:24:32 rillig Exp $");
+__RCSID("$NetBSD: init.c,v 1.80 2021/02/21 10:03:35 rillig Exp $");
 #endif
 
 #include <stdlib.h>
@@ -292,6 +292,7 @@
        }
 }
 #else
+#define debug_initstack_element(elem) do { } while (false)
 #define debug_initstack()      do { } while (false)
 #endif
 
@@ -339,55 +340,53 @@
        debug_enter();
 
        istk = initstk;
-       debug_step("pop type=%s, brace=%d remaining=%d named=%d",
-           type_name(istk->i_type != NULL ? istk->i_type : istk->i_subt),
-           istk->i_brace, istk->i_remaining, istk->i_seen_named_member);
+       debug_step("popping:");
+       debug_initstack_element(istk);
 
        initstk = istk->i_enclosing;
        free(istk);
        istk = initstk;
        lint_assert(istk != NULL);
 
-       debug_step("top type=%s, brace=%d remaining=%d named=%d",
-           type_name(istk->i_type != NULL ? istk->i_type : istk->i_subt),
-           istk->i_brace, istk->i_remaining, istk->i_seen_named_member);
-
        istk->i_remaining--;
        lint_assert(istk->i_remaining >= 0);
 
-       debug_step("top remaining=%d rhs.name=%s",
-           istk->i_remaining, namedmem != NULL ? namedmem->n_name : "*null*");
-
-       if (istk->i_remaining >= 0 && namedmem != NULL) {
+       debug_step("new top element with updated remaining:");
+       debug_initstack_element(istk);
 
-               debug_step("named remaining=%d type=%s, rhs.name=%s",
-                   istk->i_remaining, type_name(istk->i_type),
-                   namedmem->n_name);
+       if (namedmem != NULL) {
+               debug_step("initializing named member '%s'", namedmem->n_name);
 
+               /* XXX: undefined behavior if this is reached with an array? */
                for (m = istk->i_type->t_str->sou_first_member;
                     m != NULL; m = m->s_next) {
-                       debug_step("pop lhs.name=%s rhs.name=%s",
-                           m->s_name, namedmem->n_name);
+
                        if (m->s_bitfield && m->s_name == unnamed)
                                continue;
+
                        if (strcmp(m->s_name, namedmem->n_name) == 0) {
+                               debug_step("found matching member");
                                istk->i_subt = m->s_type;
+                               /* XXX: why ++? */
                                istk->i_remaining++;
+                               /* XXX: why is i_seen_named_member not set? */
                                pop_member();
                                debug_initstack();
                                debug_leave();
                                return;
                        }
                }
+
                /* undefined struct/union member: %s */
                error(101, namedmem->n_name);
-               debug_step("end rhs.name=%s", namedmem->n_name);
+
                pop_member();
                istk->i_seen_named_member = true;
                debug_initstack();
                debug_leave();
                return;
        }
+
        /*
         * If the removed element was a structure member, we must go
         * to the next structure member.
@@ -397,9 +396,11 @@
                do {
                        m = istk->i_current_object =
                            istk->i_current_object->s_next;
+                       /* XXX: can this assertion be made to fail? */
                        lint_assert(m != NULL);
                        debug_step("pop %s", m->s_name);
                } while (m->s_bitfield && m->s_name == unnamed);
+               /* XXX: duplicate code for skipping unnamed bit-fields */
                istk->i_subt = m->s_type;
        }
        debug_initstack();