Exit the "./bootstrap" step with an error if some dependencies could not be

downloaded. If dependencies fail to download, the build usually fails later.
This is apparent on our buildbots. Rather catch it early.

Patch by: me

bootstrap.1

@@ -40,6 +40,10 @@ chmod +x "$SRC_ROOT/solenv/bin/gccinstlib.pl"
 # fetch or update external tarballs
 if [ "$DO_FETCH_TARBALLS" = "yes" ]; then
     "$PERL" "$SOLARENV/bin/download_external_dependencies.pl" $SRC_ROOT/external_deps.lst
+    if [ "$?" != "0" ]; then
+        echo "*** Error downloading external dependencies, please fix the previous problems and try again ***"
+        exit 1
+    fi
 fi
 
 # ------------------------------------------------------------------------------

solenv/bin/download_external_dependencies.pl

@@ -471,20 +471,25 @@ sub Download ()
     }
 
     # Download the missing files.
+    my $all_downloaded = 1;
     for my $item (@Missing)
     {
         my ($name, $checksum, $urls) = @$item;
 
+        my $downloaded = 0;
         foreach my $url (@$urls)
         {
-            last if DownloadFile(
+            $downloaded = DownloadFile(
                 defined $checksum
                     ? $checksum->{'value'}."-".$name
                     : $name,
                 $url,
                 $checksum);
+            last if $downloaded
         }
+        $all_downloaded &&= $downloaded;
     }
+    die "some needed files could not be downloaded!" if !$all_downloaded;
 }