Module Name: src
Committed By: rillig
Date: Fri Mar 19 00:39:17 UTC 2021
Modified Files:
src/usr.bin/xlint/lint1: init.c
Log Message:
lint: extend documentation about initialization
No functional change.
To generate a diff of this commit:
cvs rdiff -u -r1.101 -r1.102 src/usr.bin/xlint/lint1/init.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/usr.bin/xlint/lint1/init.c
diff -u src/usr.bin/xlint/lint1/init.c:1.101 src/usr.bin/xlint/lint1/init.c:1.102
--- src/usr.bin/xlint/lint1/init.c:1.101 Fri Mar 19 00:19:32 2021
+++ src/usr.bin/xlint/lint1/init.c Fri Mar 19 00:39:17 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: init.c,v 1.101 2021/03/19 00:19:32 rillig Exp $ */
+/* $NetBSD: init.c,v 1.102 2021/03/19 00:39:17 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 1.101 2021/03/19 00:19:32 rillig Exp $");
+__RCSID("$NetBSD: init.c,v 1.102 2021/03/19 00:39:17 rillig Exp $");
#endif
#include <stdlib.h>
@@ -104,15 +104,29 @@ typedef struct initstack_element {
/*
* The type to be initialized at this level.
+ *
+ * On the outermost element, this is always NULL since the outermost
+ * initializer-expression may be enclosed in an optional pair of
+ * braces. This optional pair of braces is handled by the combination
+ * of i_type and i_subt.
+ *
+ * Everywhere else it is nonnull.
*/
type_t *i_type;
+
/*
- * The type that is initialized inside a further level of
- * braces. It is completely independent from i_type->t_subt.
+ * The type that will be initialized at the next initialization level,
+ * usually enclosed by another pair of braces.
*
- * For example, in 'int var = { init }', initially there is an
- * initstack_element with i_subt == int. When the '{' is processed,
- * an element with i_type == int is pushed to the stack. When the
+ * For an array, it is the element type, but without 'const'.
+ *
+ * For a struct or union type, it is one of the member types, but
+ * without 'const'.
+ *
+ * The outermost stack element has no i_type but nevertheless has
+ * i_subt. For example, in 'int var = { 12345 }', initially there is
+ * an initstack_element with i_subt 'int'. When the '{' is processed,
+ * an element with i_type 'int' is pushed to the stack. When the
* corresponding '}' is processed, the inner element is popped again.
*
* During initialization, only the top 2 elements of the stack are
@@ -143,7 +157,12 @@ typedef struct initstack_element {
sym_t *i_current_object;
/*
- * The number of remaining elements.
+ * The number of remaining elements to be used by expressions without
+ * designator.
+ *
+ * This says nothing about which members have been initialized or not
+ * since starting with C99, members may be initialized in arbitrary
+ * order by using designators.
*
* For an array of unknown size, this is always 0 and thus irrelevant.
*
