Module Name: src
Committed By: rillig
Date: Sun Mar 21 11:55:59 UTC 2021
Modified Files:
src/tests/usr.bin/xlint/lint1: msg_217.c msg_217.exp
src/usr.bin/xlint/lint1: func.c lint1.h
Log Message:
lint: fix wrong 'falls off bottom' after return in do-while
To generate a diff of this commit:
cvs rdiff -u -r1.5 -r1.6 src/tests/usr.bin/xlint/lint1/msg_217.c
cvs rdiff -u -r1.4 -r1.5 src/tests/usr.bin/xlint/lint1/msg_217.exp
cvs rdiff -u -r1.82 -r1.83 src/usr.bin/xlint/lint1/func.c
cvs rdiff -u -r1.80 -r1.81 src/usr.bin/xlint/lint1/lint1.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/tests/usr.bin/xlint/lint1/msg_217.c
diff -u src/tests/usr.bin/xlint/lint1/msg_217.c:1.5 src/tests/usr.bin/xlint/lint1/msg_217.c:1.6
--- src/tests/usr.bin/xlint/lint1/msg_217.c:1.5 Sun Mar 21 11:48:04 2021
+++ src/tests/usr.bin/xlint/lint1/msg_217.c Sun Mar 21 11:55:59 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: msg_217.c,v 1.5 2021/03/21 11:48:04 rillig Exp $ */
+/* $NetBSD: msg_217.c,v 1.6 2021/03/21 11:55:59 rillig Exp $ */
# 3 "msg_217.c"
// Test for message: function %s falls off bottom without returning value [217]
@@ -23,6 +23,9 @@ random(int n)
* 'while 0' was unreachable. This has been fixed by allowing the 'while 0'
* in a do-while-false loop to be unreachable. The same could be useful for a
* do-while-true.
+ *
+ * Before func.c 1.83 from 2021-03-21, lint wrongly reported that the function
+ * would fall off the bottom.
*/
int
do_while_return(int i)
@@ -30,7 +33,7 @@ do_while_return(int i)
do {
return i;
} while (0);
-} /*FIXME*//* expect: 217 */
+}
/*
* C99 5.1.2.2.3 "Program termination" p1 defines that as a special exception,
Index: src/tests/usr.bin/xlint/lint1/msg_217.exp
diff -u src/tests/usr.bin/xlint/lint1/msg_217.exp:1.4 src/tests/usr.bin/xlint/lint1/msg_217.exp:1.5
--- src/tests/usr.bin/xlint/lint1/msg_217.exp:1.4 Sun Mar 21 11:48:04 2021
+++ src/tests/usr.bin/xlint/lint1/msg_217.exp Sun Mar 21 11:55:59 2021
@@ -1,2 +1 @@
msg_217.c(11): warning: function random falls off bottom without returning value [217]
-msg_217.c(33): warning: function do_while_return falls off bottom without returning value [217]
Index: src/usr.bin/xlint/lint1/func.c
diff -u src/usr.bin/xlint/lint1/func.c:1.82 src/usr.bin/xlint/lint1/func.c:1.83
--- src/usr.bin/xlint/lint1/func.c:1.82 Sun Mar 21 11:38:24 2021
+++ src/usr.bin/xlint/lint1/func.c Sun Mar 21 11:55:59 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: func.c,v 1.82 2021/03/21 11:38:24 rillig Exp $ */
+/* $NetBSD: func.c,v 1.83 2021/03/21 11:55:59 rillig Exp $ */
/*
* Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,7 +37,7 @@
#include <sys/cdefs.h>
#if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: func.c,v 1.82 2021/03/21 11:38:24 rillig Exp $");
+__RCSID("$NetBSD: func.c,v 1.83 2021/03/21 11:55:59 rillig Exp $");
#endif
#include <stdlib.h>
@@ -830,11 +830,10 @@ do2(tnode_t *tn)
expr(tn, false, true, true, true);
- /*
- * The end of the loop is only reached if it is no endless loop
- * or there was a break statement which could be reached.
- */
- reached = !cstmt->c_infinite || cstmt->c_break;
+ if (cstmt->c_infinite)
+ reached = false;
+ if (cstmt->c_break)
+ reached = true;
rchflg = false;
popctrl(T_DO);
Index: src/usr.bin/xlint/lint1/lint1.h
diff -u src/usr.bin/xlint/lint1/lint1.h:1.80 src/usr.bin/xlint/lint1/lint1.h:1.81
--- src/usr.bin/xlint/lint1/lint1.h:1.80 Sun Mar 21 10:30:28 2021
+++ src/usr.bin/xlint/lint1/lint1.h Sun Mar 21 11:55:59 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: lint1.h,v 1.80 2021/03/21 10:30:28 rillig Exp $ */
+/* $NetBSD: lint1.h,v 1.81 2021/03/21 11:55:59 rillig Exp $ */
/*
* Copyright (c) 1996 Christopher G. Demetriou. All Rights Reserved.
@@ -386,10 +386,15 @@ typedef struct control_statement {
bool c_loop : 1; /* continue && break are valid */
bool c_switch : 1; /* case && break are valid */
bool c_break : 1; /* loop/switch has break */
+ /* TODO: is the break guaranteed to be
+ * reachable? */
bool c_cont : 1; /* loop has continue */
bool c_default : 1; /* switch has default */
- bool c_infinite : 1; /* break condition always false
- (for (;;), while (1)) */
+ bool c_infinite : 1; /* controlling expression always false
+ * (as in for (;;) or while (1)),
+ * there may be break statements
+ * though.
+ * TODO: rename to c_maybe_infinite */
bool c_rchif : 1; /* end of if-branch reached */
bool c_had_return_noval : 1; /* had "return;" */
bool c_had_return_value : 1; /* had "return (e);" */
