Warnings: Track variable references in &-expansions

For &-escapes which match the whole variable name, we can conveniently
track variable expansions as part of the processing.  (We don't change
any of the matching regexps.)

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/generate b/generate
index d8183d07dd9356e005d90a8160038dae4b9f3047..eb99456144302fe5e20ef5b09f22dade5702dbef 100755 (executable)
--- a/generate
+++ b/generate
@@ -263,7 +263,9 @@ sub process_input_mk ($$$$) {
            err "unknown directive &:$1 or bad argumnt syntax";
        } elsif (s{^\s*${esc}TARGETS(?:_([0-9a-zA-Z_]+))?(?=\W)}{}) {
            my $t = $1 // 'all';
-           od target_varname($var_prefix, $t);
+           my $vn = target_varname($var_prefix, $t);
+           $note_varref->($vn,1);
+           od $vn;
            $targets->{$t} //= [ ];
        }
        for (;;) {
@@ -297,7 +299,10 @@ sub process_input_mk ($$$$) {
            elsif (s{^\\\s+$}{}) { }
            elsif (s{^$esc}{}) { od "$$esclitr$$esclitr" }
            elsif (m{^(?=$caps_re)}) { od $var_prefix }
-           elsif (s{^\$([A-Za-z]\w+)}{}) { od "\$(${var_prefix}$1)" }
+           elsif (s{^\$([A-Za-z]\w+)}{}) {
+               $note_varref->($1,1);
+               od "\$(${var_prefix}$1)";
+           }
            elsif (s{^([~^]?)(?=$lc_re)}{}) { od $pfxmap{$1} }
            elsif (s{^_}{}) { od $var_prefix }
            elsif (s{^=}{}) { od $var_prefix_name }
@@ -306,13 +311,17 @@ sub process_input_mk ($$$$) {
            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='';