[PATCH 2/2] maint.mk: prohibit user reserved make flags

[Mathieu Lirzin]

* top/maint.mk (sc_makefile_user_flags_check): New rule.
---
 ChangeLog    | 3 +++
 top/maint.mk | 8 ++++++++
 2 files changed, 11 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index e324133..3721fff 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 2016-05-21  Mathieu Lirzin  <address@hidden>
 
+       maint.mk: prohibit user reserved make flags when using Automake
+       * top/maint.mk (sc_makefile_user_flags_check): New rule.
+
        prefer AM_TESTS_ENVIRONMENT to TESTS_ENVIRONMENT
        * Makefile, doc/gnulib.texi, doc/valgrind-tests.texi:
        * gnulib-tool, modules/acl-tests, modules/btowc-tests:
diff --git a/top/maint.mk b/top/maint.mk
index aa23364..21662ce 100644
--- a/top/maint.mk
+++ b/top/maint.mk
@@ -1164,6 +1164,14 @@ sc_makefile_path_separator_check:
        halt=$(msg)                                                     \
          $(_sc_search_regexp)
 
+# Verify that no make flags reserved for the user are present.
+msg = 'Do not set make flags reserved for the user'
+sc_makefile_user_flags_check:
+       @prohibit='^[^_]*(FLAGS|TESTS_ENVIRONMENT)'                     \
+       in_vc_files='akefile|\.mk$$'                                    \
+       halt=$(msg)                                                     \
+         $(_sc_search_regexp)
+
 # Check that 'make alpha' will not fail at the end of the process,
 # i.e., when pkg-M.N.tar.xz already exists (either in "." or in ../release)
 # and is read-only.
-- 
2.8.1