make: reinstate conditional skipping of command lines

Commit e90345c10 (make: allow empty commands) rearranged readline()
in a way that broke the use of conditionals within the definition
of a rule.

Add a test case to detect this.  Adjust readline() so that
conditionals are processed before returning command lines or
checking for empty lines and comments.

Remove the test for a leading tab in skip_lines().  This allows
conditionals in the definition of a rule to be indented with a
leading tab.

1 files changed, 2 insertions, 0 deletions

diff --git a/testsuite/make.tests b/testsuite/make.tests
index c92c69340..a12e50b8b 100755
--- a/testsuite/make.tests
+++ b/testsuite/make.tests
@@ -652,6 +652,8 @@ B = b
 target:
 ifeq ($(A),a)
         @echo A OK
+else
+        @echo A not OK
 endif
 ifneq "a" "$B"
         @echo B OK