Module Name: src
Committed By: rillig
Date: Sat Apr 16 13:25:27 UTC 2022
Modified Files:
src/tests/usr.bin/xlint/lint1: msg_081.c msg_100.c msg_340.c
msg_340.exp
src/usr.bin/xlint/lint1: err.c externs1.h main1.c
Log Message:
lint: model C language levels in a future-compatible way
The options -t, -s and -S are confusing because they are used
inconsistently. The option -S enables C99 features, but when using it
instead of -s, it also doesn't enable all checks required by C90 and
later. Prepare fixing of these inconsistencies by replacing the flag
variables with language levels that can be extended in a
straight-forward way as new C standards arrive.
| option | allow_trad | allow_c90 | allow_c99 | allow_c11 |
|--------|------------|-----------|-----------|-----------|
| -t | x | - | - | - |
| (none) | x | x | - | - |
| -s | - | x | - | - |
| -S | - | x | x | - |
| -Ac11 | - | x | x | x |
Each usage of the old flag variables will be inspected and migrated
individually, to clean up the subtle variations in the conditions and to
provide a simpler model.
When lint was created in 1995, its focus was migrating traditional C
code to C90 code. Lint does not help in migrating from C90 to C99 or
from C99 to C11 since there are only few silent changes, and simply
because nobody took the time to implement these migration aids. If
necessary, such migration modes could be added separately.
There is a small functional change: when the option -s is combined with
either -S or -Ac11, lint now only keeps the last of these options.
Previously, these options could be combined, leading to a mixture of
language levels, halfway between C90, C99 and C11. Especially combining
traditional C with C11 doesn't make sense, but xlint currently allows
it.
The 3 tests that accidentally specified multiple language levels have
been adjusted to a single language level.
To generate a diff of this commit:
cvs rdiff -u -r1.3 -r1.4 src/tests/usr.bin/xlint/lint1/msg_081.c \
src/tests/usr.bin/xlint/lint1/msg_100.c \
src/tests/usr.bin/xlint/lint1/msg_340.exp
cvs rdiff -u -r1.2 -r1.3 src/tests/usr.bin/xlint/lint1/msg_340.c
cvs rdiff -u -r1.159 -r1.160 src/usr.bin/xlint/lint1/err.c
cvs rdiff -u -r1.154 -r1.155 src/usr.bin/xlint/lint1/externs1.h
cvs rdiff -u -r1.59 -r1.60 src/usr.bin/xlint/lint1/main1.c
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_081.c
diff -u src/tests/usr.bin/xlint/lint1/msg_081.c:1.3 src/tests/usr.bin/xlint/lint1/msg_081.c:1.4
--- src/tests/usr.bin/xlint/lint1/msg_081.c:1.3 Sun Jan 31 11:12:07 2021
+++ src/tests/usr.bin/xlint/lint1/msg_081.c Sat Apr 16 13:25:27 2022
@@ -1,8 +1,8 @@
-/* $NetBSD: msg_081.c,v 1.3 2021/01/31 11:12:07 rillig Exp $ */
+/* $NetBSD: msg_081.c,v 1.4 2022/04/16 13:25:27 rillig Exp $ */
# 3 "msg_081.c"
-// Test for message: \a undefined in traditional C [81]
+/* Test for message: \a undefined in traditional C [81] */
-/* lint1-flags: -Stw */
+/* lint1-flags: -tw */
char str[] = "The bell\a rings"; /* expect: 81 */
Index: src/tests/usr.bin/xlint/lint1/msg_100.c
diff -u src/tests/usr.bin/xlint/lint1/msg_100.c:1.3 src/tests/usr.bin/xlint/lint1/msg_100.c:1.4
--- src/tests/usr.bin/xlint/lint1/msg_100.c:1.3 Sun Jan 31 11:12:07 2021
+++ src/tests/usr.bin/xlint/lint1/msg_100.c Sat Apr 16 13:25:27 2022
@@ -1,9 +1,9 @@
-/* $NetBSD: msg_100.c,v 1.3 2021/01/31 11:12:07 rillig Exp $ */
+/* $NetBSD: msg_100.c,v 1.4 2022/04/16 13:25:27 rillig Exp $ */
# 3 "msg_100.c"
-// Test for message: unary + is illegal in traditional C [100]
+/* Test for message: unary + is illegal in traditional C [100] */
-/* lint1-flags: -Stw */
+/* lint1-flags: -tw */
int
unary_plus(int x)
Index: src/tests/usr.bin/xlint/lint1/msg_340.exp
diff -u src/tests/usr.bin/xlint/lint1/msg_340.exp:1.3 src/tests/usr.bin/xlint/lint1/msg_340.exp:1.4
--- src/tests/usr.bin/xlint/lint1/msg_340.exp:1.3 Mon Jul 5 19:53:43 2021
+++ src/tests/usr.bin/xlint/lint1/msg_340.exp Sat Apr 16 13:25:27 2022
@@ -1 +1 @@
-msg_340.c(16): error: initialization with '[a...b]' is a GCC extension [340]
+msg_340.c(16): warning: initialization with '[a...b]' is a GCC extension [340]
Index: src/tests/usr.bin/xlint/lint1/msg_340.c
diff -u src/tests/usr.bin/xlint/lint1/msg_340.c:1.2 src/tests/usr.bin/xlint/lint1/msg_340.c:1.3
--- src/tests/usr.bin/xlint/lint1/msg_340.c:1.2 Mon Jul 5 19:53:43 2021
+++ src/tests/usr.bin/xlint/lint1/msg_340.c Sat Apr 16 13:25:27 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: msg_340.c,v 1.2 2021/07/05 19:53:43 rillig Exp $ */
+/* $NetBSD: msg_340.c,v 1.3 2022/04/16 13:25:27 rillig Exp $ */
# 3 "msg_340.c"
// Test for message: initialization with '[a...b]' is a GCC extension [340]
@@ -7,7 +7,7 @@
* In strict C mode, GCC extensions are flagged as such.
*/
-/* lint1-flags: -Ssw */
+/* lint1-flags: -Sw */
int
example(void)
Index: src/usr.bin/xlint/lint1/err.c
diff -u src/usr.bin/xlint/lint1/err.c:1.159 src/usr.bin/xlint/lint1/err.c:1.160
--- src/usr.bin/xlint/lint1/err.c:1.159 Fri Apr 8 21:29:29 2022
+++ src/usr.bin/xlint/lint1/err.c Sat Apr 16 13:25:27 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: err.c,v 1.159 2022/04/08 21:29:29 rillig Exp $ */
+/* $NetBSD: err.c,v 1.160 2022/04/16 13:25:27 rillig Exp $ */
/*
* Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,7 +37,7 @@
#include <sys/cdefs.h>
#if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: err.c,v 1.159 2022/04/08 21:29:29 rillig Exp $");
+__RCSID("$NetBSD: err.c,v 1.160 2022/04/16 13:25:27 rillig Exp $");
#endif
#include <sys/types.h>
@@ -630,12 +630,6 @@ void
va_end(ap);
}
-/*
- * XXX I think the logic is possibly somewhat screwed up here. The
- * question is, how do we want to interpret the -s and -S flags going
- * forward? We need to answer that and then we can fix this to be
- * "right"... [perry, 2 Nov 2002]
-*/
void
(c99ism)(int msgid, ...)
{
Index: src/usr.bin/xlint/lint1/externs1.h
diff -u src/usr.bin/xlint/lint1/externs1.h:1.154 src/usr.bin/xlint/lint1/externs1.h:1.155
--- src/usr.bin/xlint/lint1/externs1.h:1.154 Sat Apr 9 23:41:22 2022
+++ src/usr.bin/xlint/lint1/externs1.h Sat Apr 16 13:25:27 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: externs1.h,v 1.154 2022/04/09 23:41:22 rillig Exp $ */
+/* $NetBSD: externs1.h,v 1.155 2022/04/16 13:25:27 rillig Exp $ */
/*
* Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,24 +37,41 @@
extern int aflag;
extern bool bflag;
extern bool cflag;
-extern bool c11flag;
extern bool eflag;
extern bool Fflag;
-extern bool gflag;
extern bool hflag;
extern bool pflag;
extern bool rflag;
-extern bool sflag;
-extern bool tflag;
extern bool uflag;
extern bool vflag;
extern bool yflag;
extern bool wflag;
extern bool zflag;
-extern bool Sflag;
extern bool Tflag;
extern bool Pflag;
+extern bool allow_trad;
+extern bool allow_c90;
+extern bool allow_c99;
+extern bool allow_c11;
+extern bool allow_gcc;
+
+/*
+ * TODO: Replace the old flags with the new expressions, checking in each
+ * case whether the specific condition still makes sense. When lint was
+ * invented in 1995, it did not know about C99 mode, which makes all
+ * conditions involving tflag and sflag suspicious.
+ *
+ * In 1995, gflag meant "C90 plus GCC extensions". That definition needs to
+ * be extended to C99 and later as well to properly match "C99 + GCC" or "C11
+ * + GCC".
+ */
+#define tflag (allow_trad && !allow_c90)
+#define sflag (!allow_trad && !allow_c99)
+#define Sflag (!!allow_c99)
+#define c11flag (!!allow_c11)
+#define gflag (!!allow_gcc)
+
extern void norecover(void);
/*
Index: src/usr.bin/xlint/lint1/main1.c
diff -u src/usr.bin/xlint/lint1/main1.c:1.59 src/usr.bin/xlint/lint1/main1.c:1.60
--- src/usr.bin/xlint/lint1/main1.c:1.59 Sun Feb 27 11:40:29 2022
+++ src/usr.bin/xlint/lint1/main1.c Sat Apr 16 13:25:27 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: main1.c,v 1.59 2022/02/27 11:40:29 rillig Exp $ */
+/* $NetBSD: main1.c,v 1.60 2022/04/16 13:25:27 rillig Exp $ */
/*
* Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,7 +37,7 @@
#include <sys/cdefs.h>
#if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: main1.c,v 1.59 2022/02/27 11:40:29 rillig Exp $");
+__RCSID("$NetBSD: main1.c,v 1.60 2022/04/16 13:25:27 rillig Exp $");
#endif
#include <sys/types.h>
@@ -68,18 +68,12 @@ bool bflag;
/* Print warnings for pointer casts. */
bool cflag;
-/* Allow features from C11, C99 and C90. */
-bool c11flag;
-
/* Perform stricter checking of enum types and operations on enum types. */
bool eflag;
/* Print complete pathnames, not only the basename. */
bool Fflag;
-/* Enable some extensions of gcc */
-bool gflag;
-
/* Treat warnings as errors */
bool wflag;
@@ -98,17 +92,8 @@ bool pflag;
*/
bool rflag;
-/* Strict ANSI C mode. */
-bool sflag;
-
bool Tflag;
-/* Traditional C mode. */
-bool tflag;
-
-/* Enable C99 extensions */
-bool Sflag;
-
/* Picky flag */
bool Pflag;
@@ -124,6 +109,17 @@ bool vflag = true;
/* Complain about structures which are never defined. */
bool zflag = true;
+/*
+ * The default language level is the one that checks for compatibility
+ * between traditional C and C90. As of 2022, this default is no longer
+ * useful since most traditional C code has already been migrated.
+ */
+bool allow_trad = true;
+bool allow_c90 = true;
+bool allow_c99;
+bool allow_c11;
+bool allow_gcc;
+
err_set msgset;
sig_atomic_t fpe;
@@ -211,15 +207,30 @@ main(int argc, char *argv[])
case 'c': cflag = true; break;
case 'e': eflag = true; break;
case 'F': Fflag = true; break;
- case 'g': gflag = true; break;
+ case 'g': allow_gcc = true; break;
case 'h': hflag = true; break;
case 'p': pflag = true; break;
case 'P': Pflag = true; break;
case 'r': rflag = true; break;
- case 's': sflag = true; break;
- case 'S': Sflag = true; break;
+ case 's':
+ allow_trad = false;
+ allow_c90 = true;
+ allow_c99 = false;
+ allow_c11 = false;
+ break;
+ case 'S':
+ allow_trad = false;
+ allow_c90 = true;
+ allow_c99 = true;
+ allow_c11 = false;
+ break;
case 'T': Tflag = true; break;
- case 't': tflag = true; break;
+ case 't':
+ allow_trad = true;
+ allow_c90 = false;
+ allow_c99 = false;
+ allow_c11 = false;
+ break;
case 'u': uflag = false; break;
case 'w': wflag = true; break;
case 'v': vflag = false; break;
@@ -228,9 +239,10 @@ main(int argc, char *argv[])
case 'A':
if (strcmp(optarg, "c11") == 0) {
- c11flag = true;
- Sflag = true;
- sflag = false;
+ allow_trad = false;
+ allow_c90 = true;
+ allow_c99 = true;
+ allow_c11 = true;
} else
usage();
break;
@@ -273,7 +285,7 @@ main(int argc, char *argv[])
initdecl();
initscan();
- if (gflag && !tflag) {
+ if (allow_gcc && !tflag) {
if ((yyin = gcc_builtins()) == NULL)
err(1, "cannot open builtins");
yyparse();
