make flags analysis: fix bug in $(MFLAGS) parsing (typo-induced)

* header-vars.mk (am.make.is-running-with-option): Here.

This change fixes the failures in test 'make-dryrun.tap' (exposed by
previous commit v1.13.1d-928-g723f6d9), and also fixes a long-standing
failure of the test 'remake-gnulib-add-acsubst.sh'.  Yay!

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>

diff --git a/lib/am/header-vars.mk b/lib/am/header-vars.mk
index 37f0c871ec2b5cd3fea820e1ddeb8dcd768e74cb..4cea4aa27080db3eebe337639c23b355d4cc3817 100644 (file)
--- a/lib/am/header-vars.mk
+++ b/lib/am/header-vars.mk
@@ -168,10 +168,10 @@ DESTDIR ?=
 # implementation.  It is worthwhile to note that, when expanded
 # from the top-level make, $(MFLAGS) doesn't contain references to
 # options that take an argument, either mandatory (e.g., '-I') or
-# optional (e.g., '-O').  This *vastly* semplifies the implementation
+# optional (e.g., '-O').  This *vastly* simplifies the implementation
 # of this macro.
 am.make.is-running-with-option = \
-  $(if $(findstring $(strip $1),filter-out --%,$(MFLAGS)),true,false)
+  $(if $(findstring $(strip $1),$(filter-out --%,$(MFLAGS))),true,false)
 
 # Tell whether make is running in "dry mode".
 am.make.dry-run := $(call am.make.is-running-with-option, n)