1 #!/usr/bin/perl

     2 

     3 # Copyright (C) 2006, 2007, 2008, 2010 Apple Inc. All rights reserved.

     4 #

     5 # Redistribution and use in source and binary forms, with or without

     6 # modification, are permitted provided that the following conditions

     7 # are met:

     8 #

     9 # 1.  Redistributions of source code must retain the above copyright

    10 #     notice, this list of conditions and the following disclaimer. 

    11 # 2.  Redistributions in binary form must reproduce the above copyright

    12 #     notice, this list of conditions and the following disclaimer in the

    13 #     documentation and/or other materials provided with the distribution. 

    14 # 3.  Neither the name of Apple Inc. ("Apple") nor the names of

    15 #     its contributors may be used to endorse or promote products derived

    16 #     from this software without specific prior written permission. 

    17 #

    18 # THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY

    19 # EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

    20 # WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

    21 # DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY

    22 # DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

    23 # (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

    24 # LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

    25 # ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

    26 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

    27 # THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    28 

    29 # "check-for-weak-vtables-and-externals" script for WebKit Open Source Project

    30 

    31 # Intended to be invoked from an Xcode build step to check if there are

    32 # any weak vtables or weak externals in a target.

    33 

    34 use warnings;

    35 use strict;

    36 

    37 use File::Basename;

    38 

    39 sub touch($);

    40 

    41 my $arch = $ENV{'CURRENT_ARCH'};

    42 my $configuration = $ENV{'CONFIGURATION'};

    43 my $target = $ENV{'TARGET_NAME'};

    44 my $variant = $ENV{'CURRENT_VARIANT'};

    45 my $coverageBuild = $ENV{'WEBKIT_COVERAGE_BUILD'};

    46 my $debugRoot = $ENV{'WEBKIT_DEBUG_ROOT'};

    47 

    48 $arch = $ENV{'NATIVE_ARCH'} if !$arch; # for Xcode 2.1, which does not have CURRENT_ARCH

    49 $variant = "normal" if !$variant; # for Xcode 2.1, which does not have CURRENT_VARIANT

    50 

    51 my $executablePath = "$ENV{'TARGET_BUILD_DIR'}/$ENV{'EXECUTABLE_PATH'}";

    52 

    53 my $buildTimestampPath = $ENV{'TARGET_TEMP_DIR'} . "/" . basename($0) . ".timestamp";

    54 my $buildTimestampAge = -M $buildTimestampPath;

    55 my $executablePathAge = -M $executablePath;

    56 

    57 my $sawError = 0;

    58 

    59 if (!defined $executablePathAge || !defined $buildTimestampAge || $executablePathAge > $buildTimestampAge) {

    60     if (!open NM, "(nm -m '$executablePath' | c++filt | sed 's/^/STDOUT:/') 2>&1 |") {

    61         print "ERROR: Could not open $executablePath\n";

    62         $sawError = 1;

    63         next;

    64     }

    65     my @weakVTableClasses = ();

    66     my @weakExternalSymbols = ();

    67     while (<NM>) {

    68         if (/^STDOUT:/) {

    69             # Ignore undefined, RTTI and typeinfo symbols.

    70             next if /\bundefined\b/ or /\b__ZT[IS]/;

    71 

    72             if (/weak external vtable for (.*)$/) {

    73                 push @weakVTableClasses, $1;

    74             } elsif (/weak external (.*)$/) {

    75                 push @weakExternalSymbols, $1;

    76             }

    77         } else {

    78             print STDERR if $_ ne "nm: no name list\n";

    79         }

    80     }

    81     close NM;

    82 

    83     my $shortName = $executablePath;

    84     $shortName =~ s/.*\///;

    85 

    86     if (@weakVTableClasses) {

    87         print "ERROR: $shortName has a weak vtable in it ($executablePath)\n";

    88         print "ERROR: Fix by making sure the first virtual function in each of these classes is not an inline:\n";

    89         for my $class (sort @weakVTableClasses) {

    90             print "ERROR: class $class\n";

    91         }

    92         $sawError = 1;

    93     }

    94 

    95     if (@weakExternalSymbols) {

    96         print "ERROR: $shortName has a weak external symbol in it ($executablePath)\n";

    97         print "ERROR: A weak external symbol is generated when a symbol is defined in multiple compilation units and is also marked as being exported from the library.\n";

    98         print "ERROR: A common cause of weak external symbols is when an inline function is listed in the linker export file.\n";

    99         for my $symbol (sort @weakExternalSymbols) {

   100             print "ERROR: symbol $symbol\n";

   101         }

   102         $sawError = 1;

   103     }

   104 }

   105 

   106 if ($sawError and !$coverageBuild) {

   107     unlink $executablePath;

   108     exit 1;

   109 }

   110 

   111 touch($buildTimestampPath);

   112 

   113 exit 0;

   114 

   115 sub touch($)

   116 {

   117     my ($path) = @_;

   118     open(TOUCH, ">", $path) or die "$!";

   119     close(TOUCH);

   120 }