freebsd-skq/contrib/bmake/unit-tests/recursive.mk
Simon J. Gerraty e2eeea75eb Merge bmake-20201117
o allow env var MAKE_OBJDIR_CHECK_WRITABLE=no to skip writable
  checks in InitObjdir.  Explicit .OBJDIR target always allows
  read-only directory.

o More code cleanup and refactoring.

o More unit tests

MFC after:	1 week
2020-11-20 06:02:31 +00:00

40 lines
1.3 KiB
Makefile

# $NetBSD: recursive.mk,v 1.4 2020/11/09 20:50:56 rillig Exp $
#
# In -dL mode, a variable may get expanded before it makes sense.
# This would stop make from doing anything since the "recursive" error
# is fatal and exits immediately.
#
# The purpose of evaluating that variable early was just to detect
# whether there are unclosed variables. It might be enough to parse the
# variable value without VARE_WANTRES for that purpose.
#
# Seen in pkgsrc/x11/libXfixes, and probably many more package that use
# GNU Automake.
.MAKEFLAGS: -dL
AM_V_lt= ${am__v_lt_${V}}
am__v_lt_= ${am__v_lt_${AM_DEFAULT_VERBOSITY}}
am__v_lt_0= --silent
am__v_lt_1=
# On 2020-08-06, make reported: "Variable am__v_lt_ is recursive."
libXfixes_la_LINK= ... ${AM_V_lt} ...
# somewhere later ...
AM_DEFAULT_VERBOSITY= 1
# The purpose of the -dL flag is to detect unclosed variables. This
# can be achieved by just parsing the variable and not evaluating it.
#
# When the variable is only parsed but not evaluated, bugs in nested
# variables are not discovered. But these are hard to produce anyway,
# therefore that's acceptable. In most practical cases, the missing
# brace would be detected directly in the line where it is produced.
MISSING_BRACE_INDIRECT:= ${:U\${MISSING_BRACE}
UNCLOSED= $(MISSING_PAREN
UNCLOSED= ${MISSING_BRACE
UNCLOSED= ${MISSING_BRACE_INDIRECT}