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.

2 files changed, 13 insertions, 11 deletions

diff --git a/miscutils/make.c b/miscutils/make.c
index 871c434f8..b2edfdbb4 100644
--- a/miscutils/make.c
+++ b/miscutils/make.c
@@ -1605,9 +1605,6 @@ skip_line(const char *str1)
         int ret = cstate[clevel] & SKIP_LINE;
         int key;
 
-        if (*str1 == '\t')
-                return ret;
-
         copy = xstrdup(str1);
         q = process_line(copy);
         if ((token = gettok(&q)) != NULL) {
@@ -1754,16 +1751,19 @@ readline(FILE *fd, int want_command)
                 }
                 dispno = lineno;
 
-                if (want_command && *str == '\t')
-                        return str;
+                // Check for lines that are conditionally skipped.
+                if (posix || !skip_line(str)) {
+                        if (want_command && *str == '\t')
+                                return str;
 
-                // Check for comment lines and lines that are conditionally skipped.
-                p = str;
-                while (isblank(*p))
-                        p++;
+                        // Check for comment lines
+                        p = str;
+                        while (isblank(*p))
+                                p++;
 
-                if (*p != '\n' && *str != '#' && (posix || !skip_line(str)))
-                        return str;
+                        if (*p != '\n' && *str != '#')
+                                return str;
+                }
 
                 pos = 0;
         }
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