MFH: fix error message on `make test` when bison is not installed

diff --git a/run-tests.php b/run-tests.php
index 6404f39f04fe5b326c707881109ff1f67629c2c4..76924bedd850b5a29cd97f9f9ef5bc105ff5cca2 100755 (executable)
--- a/run-tests.php
+++ b/run-tests.php
@@ -430,7 +430,7 @@ if (!getenv('NO_INTERACTION')) {
                $failed_tests_data .= "Autoconf:\n$autoconf\n";
                $failed_tests_data .= "Libtool:\n$libtool\n";
                $failed_tests_data .= "Compiler:\n$compiler\n";
-               $failed_tests_data .= "Bison:\n". @shell_exec('bison --version'). "\n";
+               $failed_tests_data .= "Bison:\n". @shell_exec('bison --version 2>/dev/null'). "\n";
                $failed_tests_data .= "Libraries:\n$ldd\n";
                $failed_tests_data .= "\n";