Module Name: src
Committed By: rillig
Date: Fri Dec 10 23:12:44 UTC 2021
Modified Files:
src/usr.bin/make: cond.c
src/usr.bin/make/unit-tests: cond-eof.exp cond-eof.mk cond-op.exp
cond-op.mk
Log Message:
make: do not evaluate misplaced expressions in malformed conditions
This change only affects the behavior for parse errors. Syntactically
well-formed conditions work exactly as before.
To generate a diff of this commit:
cvs rdiff -u -r1.285 -r1.286 src/usr.bin/make/cond.c
cvs rdiff -u -r1.2 -r1.3 src/usr.bin/make/unit-tests/cond-eof.exp \
src/usr.bin/make/unit-tests/cond-eof.mk
cvs rdiff -u -r1.10 -r1.11 src/usr.bin/make/unit-tests/cond-op.exp
cvs rdiff -u -r1.14 -r1.15 src/usr.bin/make/unit-tests/cond-op.mk
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/make/cond.c
diff -u src/usr.bin/make/cond.c:1.285 src/usr.bin/make/cond.c:1.286
--- src/usr.bin/make/cond.c:1.285 Fri Dec 10 19:47:20 2021
+++ src/usr.bin/make/cond.c Fri Dec 10 23:12:44 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: cond.c,v 1.285 2021/12/10 19:47:20 rillig Exp $ */
+/* $NetBSD: cond.c,v 1.286 2021/12/10 23:12:44 rillig Exp $ */
/*
* Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -95,7 +95,7 @@
#include "dir.h"
/* "@(#)cond.c 8.2 (Berkeley) 1/2/94" */
-MAKE_RCSID("$NetBSD: cond.c,v 1.285 2021/12/10 19:47:20 rillig Exp $");
+MAKE_RCSID("$NetBSD: cond.c,v 1.286 2021/12/10 23:12:44 rillig Exp $");
/*
* The parsing of conditional expressions is based on this grammar:
@@ -987,7 +987,7 @@ CondParser_And(CondParser *par, bool doE
if (res == CR_ERROR)
return CR_ERROR;
- op = CondParser_Token(par, doEval);
+ op = CondParser_Token(par, false);
if (op == TOK_AND) {
if (res == CR_TRUE)
return CondParser_And(par, doEval);
Index: src/usr.bin/make/unit-tests/cond-eof.exp
diff -u src/usr.bin/make/unit-tests/cond-eof.exp:1.2 src/usr.bin/make/unit-tests/cond-eof.exp:1.3
--- src/usr.bin/make/unit-tests/cond-eof.exp:1.2 Mon Dec 14 20:28:09 2020
+++ src/usr.bin/make/unit-tests/cond-eof.exp Fri Dec 10 23:12:44 2021
@@ -1,8 +1,5 @@
-side effect
make: "cond-eof.mk" line 15: Malformed conditional (0 ${SIDE_EFFECT} ${SIDE_EFFECT2})
-side effect
make: "cond-eof.mk" line 17: Malformed conditional (1 ${SIDE_EFFECT} ${SIDE_EFFECT2})
-side effect
make: "cond-eof.mk" line 19: Malformed conditional ((0) ${SIDE_EFFECT} ${SIDE_EFFECT2})
make: Fatal errors encountered -- cannot continue
make: stopped in unit-tests
Index: src/usr.bin/make/unit-tests/cond-eof.mk
diff -u src/usr.bin/make/unit-tests/cond-eof.mk:1.2 src/usr.bin/make/unit-tests/cond-eof.mk:1.3
--- src/usr.bin/make/unit-tests/cond-eof.mk:1.2 Mon Dec 14 20:28:09 2020
+++ src/usr.bin/make/unit-tests/cond-eof.mk Fri Dec 10 23:12:44 2021
@@ -1,4 +1,4 @@
-# $NetBSD: cond-eof.mk,v 1.2 2020/12/14 20:28:09 rillig Exp $
+# $NetBSD: cond-eof.mk,v 1.3 2021/12/10 23:12:44 rillig Exp $
#
# Tests for parsing conditions, especially the end of such conditions, which
# are represented as the token TOK_EOF.
@@ -7,11 +7,11 @@ SIDE_EFFECT= ${:!echo 'side effect' 1>&2
SIDE_EFFECT2= ${:!echo 'side effect 2' 1>&2!}
# In the following conditions, ${SIDE_EFFECT} is the position of the first
-# parse error. It is always fully evaluated, even if it were not necessary
-# to expand the variable expression. This is because these syntax errors are
-# an edge case that does not occur during normal operation, therefore there
-# is no need to optimize for this case, and it would slow down the common
-# case as well.
+# parse error. Before cond.c 1.286 from 2021-12-10, it was always fully
+# evaluated, even if it was not necessary to expand the variable expression.
+# These syntax errors are an edge case that does not occur during normal
+# operation. Still, it is easy to avoid evaluating these expressions, just in
+# case they have side effects.
.if 0 ${SIDE_EFFECT} ${SIDE_EFFECT2}
.endif
.if 1 ${SIDE_EFFECT} ${SIDE_EFFECT2}
Index: src/usr.bin/make/unit-tests/cond-op.exp
diff -u src/usr.bin/make/unit-tests/cond-op.exp:1.10 src/usr.bin/make/unit-tests/cond-op.exp:1.11
--- src/usr.bin/make/unit-tests/cond-op.exp:1.10 Fri Dec 10 20:22:54 2021
+++ src/usr.bin/make/unit-tests/cond-op.exp Fri Dec 10 23:12:44 2021
@@ -1,8 +1,8 @@
make: "cond-op.mk" line 50: Malformed conditional ("!word" == !word)
make: "cond-op.mk" line 76: Malformed conditional (0 ${ERR::=evaluated})
-make: "cond-op.mk" line 80: After detecting a parse error after 0, the rest is evaluated.
+make: "cond-op.mk" line 80: A misplaced expression after 0 is not evaluated.
make: "cond-op.mk" line 84: Malformed conditional (1 ${ERR::=evaluated})
-make: "cond-op.mk" line 88: After detecting a parse error after 1, the rest is evaluated.
+make: "cond-op.mk" line 88: A misplaced expression after 1 is not evaluated.
make: "cond-op.mk" line 92: Parsing continues until here.
make: "cond-op.mk" line 95: A B C => (A || B) && C A || B && C A || (B && C)
make: "cond-op.mk" line 102: 0 0 0 => 0 0 0
Index: src/usr.bin/make/unit-tests/cond-op.mk
diff -u src/usr.bin/make/unit-tests/cond-op.mk:1.14 src/usr.bin/make/unit-tests/cond-op.mk:1.15
--- src/usr.bin/make/unit-tests/cond-op.mk:1.14 Fri Dec 10 20:22:54 2021
+++ src/usr.bin/make/unit-tests/cond-op.mk Fri Dec 10 23:12:44 2021
@@ -1,4 +1,4 @@
-# $NetBSD: cond-op.mk,v 1.14 2021/12/10 20:22:54 rillig Exp $
+# $NetBSD: cond-op.mk,v 1.15 2021/12/10 23:12:44 rillig Exp $
#
# Tests for operators like &&, ||, ! in .if conditions.
#
@@ -58,34 +58,34 @@
. error
.endif
-# As soon as the parser sees the '$', it knows that the condition will
-# be malformed. Therefore there is no point in evaluating it.
+# In the following malformed conditions, as soon as the parser sees the '$'
+# after the '0' or the '1', it knows that the condition will be malformed.
+# Therefore there is no point in evaluating the misplaced expression.
+#
+# Before cond.c 1.286 from 2021-12-10, the extra expression was evaluated
+# nevertheless, since CondParser_Or and CondParser_And asked for the expanded
+# next token, even though in this position of the condition, only comparison
+# operators, TOK_AND, TOK_OR or TOK_RPAREN are allowed.
+#
+#
+#
+#
+#
#
-# As of 2021-01-20, that part of the condition is evaluated nevertheless,
-# since CondParser_Or just requests the next token, without restricting
-# the token to the expected tokens. If the parser were to restrict the
-# valid follow tokens for the token "0" to those that can actually produce
-# a correct condition (which in this case would be comparison operators,
-# TOK_AND, TOK_OR or TOK_RPAREN), the variable expression would not have
-# to be evaluated.
-#
-# This would add a good deal of complexity to the code though, for almost
-# no benefit, especially since most expressions and conditions are side
-# effect free.
.undef ERR
.if 0 ${ERR::=evaluated}
. error
.endif
-.if ${ERR:Uundefined} == evaluated
-. info After detecting a parse error after 0, the rest is evaluated.
+.if ${ERR:Uundefined} == undefined
+. info A misplaced expression after 0 is not evaluated.
.endif
.undef ERR
.if 1 ${ERR::=evaluated}
. error
.endif
-.if ${ERR:Uundefined} == evaluated
-. info After detecting a parse error after 1, the rest is evaluated.
+.if ${ERR:Uundefined} == undefined
+. info A misplaced expression after 1 is not evaluated.
.endif
# Just in case that parsing should ever stop on the first error.
