Module Name: src
Committed By: rillig
Date: Tue May 9 15:51:33 UTC 2023
Modified Files:
src/tests/usr.bin/xlint/lint1: msg_132.c
src/usr.bin/xlint/lint1: tree.c
Log Message:
lint: track integer constraints through conditional expressions
To generate a diff of this commit:
cvs rdiff -u -r1.29 -r1.30 src/tests/usr.bin/xlint/lint1/msg_132.c
cvs rdiff -u -r1.520 -r1.521 src/usr.bin/xlint/lint1/tree.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_132.c
diff -u src/tests/usr.bin/xlint/lint1/msg_132.c:1.29 src/tests/usr.bin/xlint/lint1/msg_132.c:1.30
--- src/tests/usr.bin/xlint/lint1/msg_132.c:1.29 Tue May 9 15:45:06 2023
+++ src/tests/usr.bin/xlint/lint1/msg_132.c Tue May 9 15:51:33 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: msg_132.c,v 1.29 2023/05/09 15:45:06 rillig Exp $ */
+/* $NetBSD: msg_132.c,v 1.30 2023/05/09 15:51:33 rillig Exp $ */
# 3 "msg_132.c"
// Test for message: conversion from '%s' to '%s' may lose accuracy [132]
@@ -379,8 +379,6 @@ void
test_ic_conditional(char c1, char c2)
{
/* Both operands are representable as char. */
- /* FIXME */
- /* expect+1: warning: conversion from 'int' to 'char' may lose accuracy [132] */
ch = cond ? '?' : ':';
/*
@@ -388,14 +386,19 @@ test_ic_conditional(char c1, char c2)
* warns about a narrowing conversion from 'int' to signed type
* 'char'.
*/
- /* FIXME */
- /* expect+1: warning: conversion from 'int' to 'char' may lose accuracy [132] */
ch = cond ? c1 : c2;
- /* FIXME */
+ /*
+ * Mixing s8 and u8 results in a number from -128 to 255, which does
+ * not necessarily fit into s8.
+ */
/* expect+1: warning: conversion from 'int' to 'signed char' may lose accuracy [132] */
s8 = cond ? s8 : u8;
+ /*
+ * Mixing s8 and u8 results in a number from -128 to 255, which does
+ * not necessarily fit into u8.
+ */
/* expect+1: warning: conversion from 'int' to 'unsigned char' may lose accuracy [132] */
u8 = cond ? s8 : u8;
}
Index: src/usr.bin/xlint/lint1/tree.c
diff -u src/usr.bin/xlint/lint1/tree.c:1.520 src/usr.bin/xlint/lint1/tree.c:1.521
--- src/usr.bin/xlint/lint1/tree.c:1.520 Tue May 9 15:45:06 2023
+++ src/usr.bin/xlint/lint1/tree.c Tue May 9 15:51:33 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: tree.c,v 1.520 2023/05/09 15:45:06 rillig Exp $ */
+/* $NetBSD: tree.c,v 1.521 2023/05/09 15:51:33 rillig Exp $ */
/*
* Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,7 +37,7 @@
#include <sys/cdefs.h>
#if defined(__RCSID)
-__RCSID("$NetBSD: tree.c,v 1.520 2023/05/09 15:45:06 rillig Exp $");
+__RCSID("$NetBSD: tree.c,v 1.521 2023/05/09 15:51:33 rillig Exp $");
#endif
#include <float.h>
@@ -255,6 +255,20 @@ ic_shr(const type_t *tp, integer_constra
}
static integer_constraints
+ic_cond(integer_constraints a, integer_constraints b)
+{
+ integer_constraints c;
+
+ c.smin = a.smin < b.smin ? a.smin : b.smin;
+ c.smax = a.smax > b.smax ? a.smax : b.smax;
+ c.umin = a.umin < b.umin ? a.umin : b.umin;
+ c.umax = a.umax > b.umax ? a.umax : b.umax;
+ c.bset = a.bset | b.bset;
+ c.bclr = a.bclr & b.bclr;
+ return c;
+}
+
+static integer_constraints
ic_expr(const tnode_t *tn)
{
integer_constraints lc, rc;
@@ -289,6 +303,10 @@ ic_expr(const tnode_t *tn)
lc = ic_expr(tn->tn_left);
rc = ic_expr(tn->tn_right);
return ic_bitor(lc, rc);
+ case QUEST:
+ lc = ic_expr(tn->tn_right->tn_left);
+ rc = ic_expr(tn->tn_right->tn_right);
+ return ic_cond(lc, rc);
default:
return ic_any(tn->tn_type);
}
@@ -3363,6 +3381,12 @@ can_represent(const type_t *tp, const tn
if ((~c.bclr & ~nmask) == 0)
return true;
+ integer_constraints tpc = ic_any(tp);
+ if (is_uinteger(tp->t_tspec)
+ ? tpc.umin <= c.umin && tpc.umax >= c.umax
+ : tpc.smin <= c.smin && tpc.smax >= c.smax)
+ return true;
+
return false;
}
