8 # Scan output of "nm -o -g bin/blib.a" and build up symbol cross-ref table
12 ( my $object, my $type, my $symbol ) = /^.*?:(.*?\.o):.*?\s(\S)\s(.*)$/;
13 my $category = $type eq 'U' ? "requires" : "provides";
14 $symbols->{$symbol}->{$category}->{$object} = 1;
17 # Add symbols that we know will be generated or required by the linker
19 while ( ( my $symbol, my $info ) = each %$symbols ) {
20 $info->{requires}->{LINKER} = 1 if $symbol =~ /^obj_/;
22 $symbols->{$_}->{provides}->{LINKER} = 1
23 foreach qw ( _prefix _eprefix _decompress _edecompress _text
24 _etext _data _edata _bss _ebss _end );
26 # Check for multiply defined, never-defined and unused symbols
29 while ( ( my $symbol, my $info ) = each %$symbols ) {
30 my @provides = keys %{$info->{provides}};
31 my @requires = keys %{$info->{requires}};
33 if ( @provides == 0 ) {
34 # No object provides this symbol
35 $problems->{$_}->{nonexistent}->{$symbol} = 1 foreach @requires;
36 } elsif ( @provides > 1 ) {
37 # Symbol defined in multiple objects
38 $problems->{$_}->{multiples}->{$symbol} = 1 foreach @provides;
40 if ( @requires == 0 ) {
42 $problems->{$_}->{unused}->{$symbol} = 1 foreach @provides;
46 # Print out error messages
50 foreach my $object ( sort keys %$problems ) {
51 my @nonexistent = sort keys %{$problems->{$object}->{nonexistent}};
52 my @multiples = sort keys %{$problems->{$object}->{multiples}};
53 my @unused = sort keys %{$problems->{$object}->{unused}};
55 print "WARN $object provides unused symbol $_\n" foreach @unused;
57 print "ERR $object requires non-existent symbol $_\n" foreach @nonexistent;
58 $errors += @nonexistent;
59 foreach my $symbol ( @multiples ) {
60 my @other_objects = sort grep { $_ ne $object }
61 keys %{$symbols->{$symbol}->{provides}};
62 print "ERR $object provides symbol $symbol"
63 ." (also provided by @other_objects)\n";
65 $errors += @multiples;
68 print "$errors error(s), $warnings warning(s)\n";
69 exit ( $errors ? 1 : 0 );