 @@ -12,14 +12,24 @@ Parse_PushInput: file directive-include-
 Parse_PushInput: file directive-include-guard-varname-indirect.tmp, line 1
 Parse_PushInput: file directive-include-guard-late-assignment.tmp, line 1
 Parse_PushInput: file directive-include-guard-late-assignment.tmp, line 1
 Parse_PushInput: file directive-include-guard-two-conditions.tmp, line 1
 Parse_PushInput: file directive-include-guard-two-conditions.tmp, line 1
 Parse_PushInput: file directive-include-guard-already-set.tmp, line 1
 Parse_PushInput: file directive-include-guard-already-set.tmp, line 1
 Parse_PushInput: file directive-include-guard-twice.tmp, line 1
 Parse_PushInput: file directive-include-guard-twice.tmp, line 1
 Parse_PushInput: file directive-include-guard-reuse.tmp, line 1
 Parse_PushInput: file directive-include-guard-reuse.tmp, line 1
 Parse_PushInput: file directive-include-guard-swapped.tmp, line 1
 Parse_PushInput: file directive-include-guard-swapped.tmp, line 1
 Parse_PushInput: file directive-include-guard-undef-between.tmp, line 1
 Parse_PushInput: file directive-include-guard-undef-between.tmp, line 1
 Parse_PushInput: file directive-include-guard-undef-inside.tmp, line 1
 Parse_PushInput: file directive-include-guard-undef-inside.tmp, line 1
 Parse_PushInput: file directive-include-guard-if-elif.tmp, line 1
 Parse_PushInput: file directive-include-guard-if-elif.tmp, line 1
 Parse_PushInput: file directive-include-guard-if-else.tmp, line 1
 Parse_PushInput: file directive-include-guard-if-else.tmp, line 1
 Parse_PushInput: file directive-include-guard-inner-if-elif-else.tmp, line 1
 Parse_PushInput: file directive-include-guard-inner-if-elif-else.tmp, line 1
 exit status 0

 @@ -1,27 +1,30 @@
-# $NetBSD: directive-include-guard.mk,v 1.1 2023/06/16 09:25:13 rillig Exp $
+# $NetBSD: directive-include-guard.mk,v 1.2 2023/06/18 19:16:51 rillig Exp $
+#
 # Tests for multiple-inclusion guards in makefiles.
+#
 # A file that is guarded by a multiple-inclusion guard has the following form:
+#
 #	.ifndef GUARD_NAME
 #	GUARD_NAME=	# any value
 #	...
 #	.endif
+#
-# When such a file is included for the second time, it has no effect as all
+# When such a file is included for the second time, it has no effect, as all
 # its content is skipped.
+#
 # See also:
 #	https://gcc.gnu.org/onlinedocs/cppinternals/Guard-Macros.html
+#
 # TODO: In these cases, do not include the file, to increase performance.
 # This is the canonical form of a multiple-inclusion guard.
 INCS+=	guarded-ifndef
 LINES.guarded-ifndef= \
 	'.ifndef GUARDED_IFNDEF' \
 	'GUARDED_IFNDEF=' \
 	'.endif'
 # Comments and empty lines have no influence on the multiple-inclusion guard.
 INCS+=	comments
 LINES.comments= \
 @@ -56,39 +59,44 @@ LINES.varname-mismatch= \
 	'OTHER_NAME=' \
 	'.endif'
 # The variable name in the assignment must only contain alphanumeric
 # characters and underscores, in particular, it must not be a dynamically
 # computed name.
 INCS+=	varname-indirect
 LINES.varname-indirect= \
 	'.ifndef VARNAME_INDIRECT' \
 	'VARNAME_$${:UINDIRECT}=' \
 	'.endif'
 # The variable assignment for the guard must directly follow the conditional.
+#
 # This requirement may be dropped entirely later, as the guard variable could
 # also be undefined while reading the file or at a later point, and as long as
 # the implementation checks the guard variable before skipping the file, the
 # optimization is still valid.
 INCS+=	late-assignment
 LINES.late-assignment= \
 	'.ifndef LATE_ASSIGNMENT' \
 	'OTHER=' \
 	'LATE_ASSIGNMENT=' \
 	'.endif'
 # There must be no other condition between the guard condition and the
 # variable assignment.
 INCS+=	two-conditions
 LINES.two-conditions= \
 	'.ifndef TWO_CONDITIONS' \
-	'.  if 0' \
+	'.  if 1' \
 	'TWO_CONDITIONS=' \
 	'.  endif' \
 	'.endif'
 # If the guard variable is already set before the file is included for the
 # first time, that file is not considered to be guarded.  It's a situation
 # that is uncommon in practice.
 INCS+=	already-set
 LINES.already-set= \
 	'.ifndef ALREADY_SET' \
 	'ALREADY_SET=' \
 	'.endif'
 ALREADY_SET=
 @@ -109,32 +117,84 @@ LINES.twice= \
 # variable names.  Typical choices are ${PROJECT}_${DIR}_${FILE}_MK.
 INCS+=	reuse
 LINES.reuse= \
 	${LINES.guarded-if}
 # The conditional must come before the assignment, otherwise the conditional
 # is useless, as it always evaluates to false.
 INCS+=	swapped
 LINES.swapped= \
 	'SWAPPED=' \
 	'.ifndef SWAPPED' \
 	'.endif'
 # If the guard variable is undefined at some later point, the guarded file is
 # included again.
 INCS+=	undef-between
 LINES.undef-between= \
 	'.ifndef UNDEF_BETWEEN' \
 	'UNDEF_BETWEEN=' \
 	'.endif'
 # If the guarded file undefines the guard variable, the guarded file is
 # included again.
 INCS+=	undef-inside
 LINES.undef-inside= \
 	'.ifndef UNDEF_INSIDE' \
 	'UNDEF_INSIDE=' \
 	'.undef UNDEF_INSIDE' \
 	'.endif'
 # The outermost '.if' must not have an '.elif' branch.
 INCS+=	if-elif
 LINES.if-elif = \
 	'.ifndef IF_ELIF' \
 	'IF_ELIF=' \
 	'.elif 1' \
 	'.endif'
 # The outermost '.if' must not have an '.else' branch.
 INCS+=	if-else
 LINES.if-else = \
 	'.ifndef IF_ELSE' \
 	'IF_ELSE=' \
 	'.else' \
 	'.endif'
 # The inner '.if' directives may have an '.elif' or '.else'.
 INCS+=	inner-if-elif-else
 LINES.inner-if-elif-else = \
 	'.ifndef INNER_IF_ELIF_ELSE' \
 	'INNER_IF_ELIF_ELSE=' \
 	'.  if 0' \
 	'.  elif 0' \
 	'.  else' \
 	'.  endif' \
 	'.  if 0' \
 	'.  elif 1' \
 	'.  else' \
 	'.  endif' \
 	'.  if 1' \
 	'.  elif 1' \
 	'.  else' \
 	'.  endif' \
 	'.endif'
 # Include each of the files twice.  The directive-include-guard.exp file
 # contains a single entry for the files whose multiple-inclusion guard works,
 # and two entries for the files that are not protected against multiple
 # inclusion.
+#
 # Some debug output lines are suppressed in the .exp file, see ./Makefile.
 .for i in ${INCS}
 .  for fname in directive-include-guard-$i.tmp
 _!=	printf '%s\n' ${LINES.$i} > ${fname}
 .MAKEFLAGS: -dp
 .include "${.CURDIR}/${fname}"
 .undef ${i:Mundef-between:%=UNDEF_BETWEEN}
 .include "${.CURDIR}/${fname}"
 .MAKEFLAGS: -d0
 _!=	rm ${fname}
 .  endfor
 .endfor
 all: