Module Name: src
Committed By: rillig
Date: Mon Mar 15 18:56:38 UTC 2021
Modified Files:
src/usr.bin/make: var.c
src/usr.bin/make/unit-tests: varmod-assign.exp varmod-assign.mk
Log Message:
make: fix double varname expansion in the variable modifier '::='
This is an edge case that doesn't occur in practice since pretty much
nobody dares to use variable names that contain an actual '$' in their
name. This is not about the fairly common VAR.${param} (as written in
the makefile), but instead about the variable whose name is literally
'VAR.${param}'.
The test demonstrates that after the fix, the variable name is taken
exactly as-is for the simple assignment modifier '::='. There are no
such tests for the modifiers '::+=', '::!=' and '::?=', but that's ok.
The code in ApplyModifier_Assign would look assymetrical and suspicious
enough if one of these modifiers would expand its variable name and the
others wouldn't.
To generate a diff of this commit:
cvs rdiff -u -r1.887 -r1.888 src/usr.bin/make/var.c
cvs rdiff -u -r1.10 -r1.11 src/usr.bin/make/unit-tests/varmod-assign.exp
cvs rdiff -u -r1.11 -r1.12 src/usr.bin/make/unit-tests/varmod-assign.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/var.c
diff -u src/usr.bin/make/var.c:1.887 src/usr.bin/make/var.c:1.888
--- src/usr.bin/make/var.c:1.887 Mon Mar 15 16:51:14 2021
+++ src/usr.bin/make/var.c Mon Mar 15 18:56:37 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: var.c,v 1.887 2021/03/15 16:51:14 rillig Exp $ */
+/* $NetBSD: var.c,v 1.888 2021/03/15 18:56:37 rillig Exp $ */
/*
* Copyright (c) 1988, 1989, 1990, 1993
@@ -140,7 +140,7 @@
#include "metachar.h"
/* "@(#)var.c 8.3 (Berkeley) 3/19/94" */
-MAKE_RCSID("$NetBSD: var.c,v 1.887 2021/03/15 16:51:14 rillig Exp $");
+MAKE_RCSID("$NetBSD: var.c,v 1.888 2021/03/15 18:56:37 rillig Exp $");
typedef enum VarFlags {
VFL_NONE = 0,
@@ -3425,10 +3425,9 @@ ok:
VarFreeEnv(gv);
}
- /* XXX: Expanding the variable name at this point sounds wrong. */
switch (op[0]) {
case '+':
- Var_AppendExpand(scope, expr->var->name.str, val);
+ Var_Append(scope, expr->var->name.str, val);
break;
case '!': {
const char *errfmt;
@@ -3436,7 +3435,7 @@ ok:
if (errfmt != NULL)
Error(errfmt, val);
else
- Var_SetExpand(scope, expr->var->name.str, cmd_output);
+ Var_Set(scope, expr->var->name.str, cmd_output);
free(cmd_output);
break;
}
@@ -3445,7 +3444,7 @@ ok:
break;
/* FALLTHROUGH */
default:
- Var_SetExpand(scope, expr->var->name.str, val);
+ Var_Set(scope, expr->var->name.str, val);
break;
}
Expr_SetValueRefer(expr, "");
Index: src/usr.bin/make/unit-tests/varmod-assign.exp
diff -u src/usr.bin/make/unit-tests/varmod-assign.exp:1.10 src/usr.bin/make/unit-tests/varmod-assign.exp:1.11
--- src/usr.bin/make/unit-tests/varmod-assign.exp:1.10 Mon Mar 15 18:46:05 2021
+++ src/usr.bin/make/unit-tests/varmod-assign.exp Mon Mar 15 18:56:38 2021
@@ -6,13 +6,10 @@ Var_Parse: ${${VARNAME}::=assigned-value
Var_Parse: ${VARNAME}::=assigned-value} (eval-defined)
Applying ${VAR.${param}::...} to "initial-value" (eval-defined, none, regular)
Modifier part: "assigned-value"
-Var_Parse: ${param} (eval)
-Global:VAR.twice = assigned-value
+Global:VAR.${param} = assigned-value
Result of ${VAR.${param}::=assigned-value} is "" (eval-defined, none, regular)
-Var_Parse: $ for symmetry with the usual assignment operators. (eval)
-make: "varmod-assign.mk" line 139: FIXME: don't expand the variable name twice here, for symmetry with the usual assignment operators.
-Var_Parse: ${${VARNAME}} != "initial-value" (eval-defined)
-Var_Parse: ${VARNAME}} != "initial-value" (eval-defined)
+Var_Parse: ${${VARNAME}} != "assigned-value" (eval-defined)
+Var_Parse: ${VARNAME}} != "assigned-value" (eval-defined)
Global:.MAKEFLAGS = -r -k -d v -d
Global:.MAKEFLAGS = -r -k -d v -d 0
mod-assign: first=1.
Index: src/usr.bin/make/unit-tests/varmod-assign.mk
diff -u src/usr.bin/make/unit-tests/varmod-assign.mk:1.11 src/usr.bin/make/unit-tests/varmod-assign.mk:1.12
--- src/usr.bin/make/unit-tests/varmod-assign.mk:1.11 Mon Mar 15 18:46:05 2021
+++ src/usr.bin/make/unit-tests/varmod-assign.mk Mon Mar 15 18:56:38 2021
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-assign.mk,v 1.11 2021/03/15 18:46:05 rillig Exp $
+# $NetBSD: varmod-assign.mk,v 1.12 2021/03/15 18:56:38 rillig Exp $
#
# Tests for the obscure ::= variable modifiers, which perform variable
# assignments during evaluation, just like the = operator in C.
@@ -132,13 +132,10 @@ ${VARNAME}= initial-value # Sets 'VAR.${
.if ${${VARNAME}::=assigned-value} # Here the variable name gets expanded once
. error # too often.
.endif
-.if !defined(VAR.twice)
-. error # FIXME: This is the unwanted current behavior.
-.else
-. info FIXME: don't expand the variable name twice here, $\
- for symmetry with the usual assignment operators.
+.if defined(VAR.twice)
+. error The variable name in the '::=' modifier is expanded once too often.
.endif
-.if ${${VARNAME}} != "initial-value"
+.if ${${VARNAME}} != "assigned-value"
. error
.endif
.MAKEFLAGS: -d0
