Warnings: Track basic $-references

[subdirmk.git] / generate

diff --git a/generate b/generate
index 9be1cfb8bf4b5d9f6ceabb91bd1174724cf8a69b..d8183d07dd9356e005d90a8160038dae4b9f3047 100755 (executable)
--- a/generate
+++ b/generate
@@ -152,6 +152,8 @@ Makefile run-main.mk:
 END
 }
 
+our %varref;
+
 our ($dir_prefix, $dir_suffix, $dir_name,
      $var_prefix, $var_prefix_name);
 
@@ -235,7 +237,18 @@ sub process_input_mk ($$$$) {
        $ddbl = (shift @nest)[1];
     };
 
+    # Our detection of variable settings does not have to be completely
+    # accurate, since it is only going to be used for advice to the user.
+    my $note_varref = sub {
+       my ($vn,$amp) = @_;
+       $varref{$vn}{$amp}{"$f:$."} = 1;
+    };
+
     while (<$input>) {
+       if (m#^\s*($esc)?(\w+)\s*(?:=|\+=|\?=|:=)# ||
+           m#^\s*(?:$esc\:macro|define)\s+($esc)?(\S+)\s#) {
+           $note_varref->($2,!!$1);
+       }
        if (s#^\s*$esc\:changequote\s+(\S+)\s+$##) {
            $$esclitr = $1;
            $set_esc->();
@@ -257,8 +270,8 @@ sub process_input_mk ($$$$) {
            err 'cannot $-double &-processed RHS of directive'
                if $ddbl && defined $buffering_output;
            unless ($nest[0][0] eq 'eval'
-                   ? s{^(.*?)($esc|[{}])}{}
-                   : s{^(.*?)($esc)}{}) { od $_; last; }
+                   ? s{^(.*?)($esc|\$|[{}])}{}
+                   : s{^(.*?)($esc|\$)}{}) { od $_; last; }
            od $1;
            if ($2 eq '{') {
                od $2;
@@ -270,6 +283,14 @@ sub process_input_mk ($$$$) {
                $pop_nest->('eval');
                od '}';
                next;
+           } elsif ($2 eq '$') {
+               od $2;
+               if (s{^\$}{}) { od $&; }
+               elsif (m{^\(($esc)?([^()\$]+)\)} ||
+                      m{^\{($esc)?([^{}\$]+)\}}) {
+                   $note_varref->($2,!!$1);
+               }
+               next;
            }
            if (s{^\\$esc}{}) { od "$$esclitr" }
            elsif (s{^\\\$}{}) { oud '$' }
@@ -440,6 +461,20 @@ sub process_tree() {
     oraw "include \$(SUBDIRMK_MAKEFILES)\n";
 }
 
+sub print_varref_warnings () {
+    foreach my $vn (sort keys %varref) {
+       my $vv = $varref{$vn};
+       next unless $vv->{''} && $vv->{1};
+       print STDERR "subdirmk: warning: saw both $vn and &$vn\n";
+       foreach my $amp ('', 1) {
+           printf STDERR " saw %s%s at %s\n",
+               ($amp ? '&' : ''), $vn, $_
+               foreach sort keys %{ $vv->{$amp} };
+       }
+    }
+}
+
 build_tree();
 process_tree();
+print_varref_warnings();
 install_output_files();