X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ian/git?p=subdirmk.git;a=blobdiff_plain;f=generate;h=13809183f4050d6eafe2b2096716adad3dcd48eb;hp=4014471a43019cec4e683d1d3ab60e4b82e6edc8;hb=a57defbff4c95ddb492dbd0c605611d11192dde5;hpb=6107afd5a8723f6336d4eb07e04fa231542e0a70

diff --git a/generate b/generate
index 4014471..1380918 100755
--- 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);
 
@@ -176,6 +178,11 @@ sub err ($) {
     die "subdirmk: ${err_file}:$.: $m\n";
 }
 
+sub wrn ($) {
+    my ($m) = @_;
+    print STDERR "subdirmk: warning: ${err_file}:$.: $m\n";
+}
+
 sub ddbl_only ($) {
     my ($e) = @_;
     return if $ddbl;
@@ -216,6 +223,7 @@ sub process_input_mk ($$$$) {
 
     local $ddbl;
     my @nest = (['']);
+    my $evalcall_brackets;
 
     my $push_nest = sub {
 	my ($nk, $nndbl, $what) = @_;
@@ -229,7 +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+$##) {
 	    $$esclitr = $1;
 	    $set_esc->();
@@ -244,23 +263,39 @@ sub process_input_mk ($$$$) {
 	    err "unknown directive &:$1 or bad argumnt syntax";
 	} elsif (s{^\s*${esc}TARGETS(?:_([0-9a-zA-Z_]+))?(?=\W)}{}) {
 	    my $t = $1 // 'all';
-	    od target_varname($var_prefix, $t);
+	    my $vn = target_varname($var_prefix, $t);
+	    $note_varref->($vn,1);
+	    od $vn;
 	    $targets->{$t} //= [ ];
 	}
 	for (;;) {
 	    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 '{') {
-		$ddbl++;
+		od $2;
+		$evalcall_brackets++;
 		next;
 	    } elsif ($2 eq '}') {
-		next if --$ddbl;
+		od $2;
+		next if --$evalcall_brackets;
 		$pop_nest->('eval');
-		od '}}';
+		od '}';
+		next;
+	    } elsif ($2 eq '$') {
+		od $2;
+		if (s{^\$}{}) { od $&; }
+		elsif (m{^[a-zA-Z]\w}) {
+		    wrn
+		    'possibly confusing unbracketed single-char $-expansion';
+		}
+		elsif (m{^\(($esc)?([^()\$]+)\)} ||
+		       m{^\{($esc)?([^{}\$]+)\}}) {
+		    $note_varref->($2,!!$1);
+	        }
 		next;
 	    }
 	    if (s{^\\$esc}{}) { od "$$esclitr" }
@@ -268,7 +303,10 @@ sub process_input_mk ($$$$) {
 	    elsif (s{^\\\s+$}{}) { }
 	    elsif (s{^$esc}{}) { od "$$esclitr$$esclitr" }
 	    elsif (m{^(?=$caps_re)}) { od $var_prefix }
-	    elsif (s{^\$([A-Za-z]\w+)}{}) { od "\$(${var_prefix}$1)" }
+	    elsif (s{^\$([A-Za-z]\w+)}{}) {
+		$note_varref->($1,1);
+		od "\$(${var_prefix}$1)";
+	    }
 	    elsif (s{^([~^]?)(?=$lc_re)}{}) { od $pfxmap{$1} }
 	    elsif (s{^_}{}) { od $var_prefix }
 	    elsif (s{^=}{}) { od $var_prefix_name }
@@ -277,12 +315,17 @@ sub process_input_mk ($$$$) {
 	    elsif (s{^([~^])\.}{}) { od $srcdirmap{$1} }
 	    elsif (s{^\$\-}{}) { $ddbl=undef; }
 	    elsif (s{^\$\+}{}) { $ddbl=1; }
-	    elsif (s{^\$\(}{}) { ddbl_only($&); oud "\$("; }
+	    elsif (s{^\$\(}{}) {
+		ddbl_only($&); oud "\$(";
+		$note_varref->($2,!!$1) if m{^($esc)?([^()\$]+\))};
+	    }
 	    elsif (s{^\$(\d+)}{}) { ddbl_only($&); oud "\$($1)"; }
 	    elsif (s{^\$\{}{}) {
 		err 'macro invocation cannot be re-$-doubled' if $ddbl;
 		od '${eval ${call ';
+		$evalcall_brackets = 1;
 		$push_nest->('eval',1, '&${...}');
+		$note_varref->($2,!!$1) if m{^\s*($esc)?([^,{}\$]+)};
 	    } elsif (s{^([~^]?)(?=[ \t])}{}) {
 		my $prefix = $pfxmap{$1} // die "internal error ($1?)";
 		my $after='';
@@ -431,6 +474,24 @@ sub process_tree() {
     oraw "include \$(SUBDIRMK_MAKEFILES)\n";
 }
 
+sub flmap ($) { local ($_) = @_; s{:(\d+)$}{ sprintf ":%10d", $1 }e; $_; }
+
+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, $_
+		foreach
+		sort { flmap($a) cmp flmap($b) }
+		keys %{ $vv->{$amp} };
+	}
+    }
+}
+
 build_tree();
 process_tree();
+print_varref_warnings();
 install_output_files();