Append CFLAGS and LDFLAGS to their Config.pm counterparts in EU::CBuilder

Since ExtUtils::CBuilder 0.27_04 (bleadperl commit 06e8058f27e4),
CFLAGS and LDFLAGS from the environment have overridden the Config.pm
ccflags and ldflags settings. This can cause binary incompatibilities
between the core Perl and extensions built with EU::CBuilder.

Append to the Config.pm values rather than overriding them.

2 files changed, 28 insertions, 3 deletions

diff --git a/dist/ExtUtils-CBuilder/lib/ExtUtils/CBuilder/Base.pm b/dist/ExtUtils-CBuilder/lib/ExtUtils/CBuilder/Base.pm
index b57231272a..2255c51259 100644
--- a/dist/ExtUtils-CBuilder/lib/ExtUtils/CBuilder/Base.pm
+++ b/dist/ExtUtils-CBuilder/lib/ExtUtils/CBuilder/Base.pm
@@ -40,11 +40,13 @@ sub new {
     $self->{config}{$k} = $v unless exists $self->{config}{$k};
   }
   $self->{config}{cc} = $ENV{CC} if defined $ENV{CC};
-  $self->{config}{ccflags} = $ENV{CFLAGS} if defined $ENV{CFLAGS};
+  $self->{config}{ccflags} = join(" ", $self->{config}{ccflags}, $ENV{CFLAGS})
+     if defined $ENV{CFLAGS};
   $self->{config}{cxx} = $ENV{CXX} if defined $ENV{CXX};
   $self->{config}{cxxflags} = $ENV{CXXFLAGS} if defined $ENV{CXXFLAGS};
   $self->{config}{ld} = $ENV{LD} if defined $ENV{LD};
-  $self->{config}{ldflags} = $ENV{LDFLAGS} if defined $ENV{LDFLAGS};
+  $self->{config}{ldflags} = join(" ", $self->{config}{ldflags}, $ENV{LDFLAGS})
+     if defined $ENV{LDFLAGS};
 
   unless ( exists $self->{config}{cxx} ) {
     my ($ccpath, $ccbase, $ccsfx ) = fileparse($self->{config}{cc}, qr/\.[^.]*/);
diff --git a/dist/ExtUtils-CBuilder/t/04-base.t b/dist/ExtUtils-CBuilder/t/04-base.t
index db0ef984d4..49819a178a 100644
--- a/dist/ExtUtils-CBuilder/t/04-base.t
+++ b/dist/ExtUtils-CBuilder/t/04-base.t
@@ -1,7 +1,7 @@
 #! perl -w
 
 use strict;
-use Test::More tests => 50;
+use Test::More tests => 64;
 use Config;
 use Cwd;
 use File::Path qw( mkpath );
@@ -328,6 +328,29 @@ is_deeply( $mksymlists_args,
     "_prepare_mksymlists_args(): got expected arguments for Mksymlists",
 );
 
+my %testvars = (
+    CFLAGS  => 'ccflags',
+    LDFLAGS => 'ldflags',
+);
+
+while (my ($VAR, $var) = each %testvars) {
+    local $ENV{$VAR};
+    $base = ExtUtils::CBuilder::Base->new( quiet => 1 );
+    ok( $base, "ExtUtils::CBuilder::Base->new() returned true value" );
+    isa_ok( $base, 'ExtUtils::CBuilder::Base' );
+    like($base->{config}{$var}, qr/\Q$Config{$var}/,
+        "honours $var from Config.pm");
+
+    $ENV{$VAR} = "-foo -bar";
+    $base = ExtUtils::CBuilder::Base->new( quiet => 1 );
+    ok( $base, "ExtUtils::CBuilder::Base->new() returned true value" );
+    isa_ok( $base, 'ExtUtils::CBuilder::Base' );
+    like($base->{config}{$var}, qr/\Q$ENV{$VAR}/,
+        "honours $VAR from the environment");
+    like($base->{config}{$var}, qr/\Q$Config{$var}/,
+        "doesn't override $var from Config.pm with $VAR from the environment");
+}
+
 #####
 
 for ($source_file, $object_file, $lib_file) {