NetBSD/usr.bin/make/unit-tests/deptgt.mk

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# $NetBSD: deptgt.mk,v 1.11 2021/04/04 10:13:09 rillig Exp $
#
# Tests for special targets like .BEGIN or .SUFFIXES in dependency
# declarations.
# TODO: Implementation
# Just in case anyone tries to compile several special targets in a single
# dependency line: That doesn't work, and make immediately rejects it.
.SUFFIXES .PHONY: .c.o
# The following lines demonstrate how 'targets' is set and reset during
# parsing of dependencies. To see it in action, set breakpoints in:
#
# ParseDependency at the beginning
# FinishDependencyGroup at "targets = NULL"
# Parse_File at "Lst_Free(targets)"
# Parse_File at "targets = Lst_New()"
# ParseLine_ShellCommand at "targets == NULL"
#
# Keywords:
# parse.c:targets
target1 target2: sources # targets := [target1, target2]
: command1 # targets == [target1, target2]
: command2 # targets == [target1, target2]
VAR=value # targets := NULL
: command3 # parse error, since targets == NULL
# In a dependency declaration, the list of targets can be empty.
# It doesn't matter whether the empty string is generated by a variable
# expression or whether it is just omitted.
.MAKEFLAGS: -dp
${:U}: empty-source
: command for empty targets list
: empty-source
: command for empty targets list
.MAKEFLAGS: -d0
# Just to show that a malformed expression is only expanded once in
# ParseDependencyTargetWord. The only way to produce an expression that
# is well-formed on the first expansion and ill-formed on the second
# expansion would be to use the variable modifier '::=' to modify the
# targets. This in turn would be such an extreme and unreliable edge case
# that nobody uses it.
$$$$$$$${:U:Z}:
all:
@:;