diff --git a/qmake/project.cpp b/qmake/project.cpp
index 3957144..0508c31 100644
--- a/qmake/project.cpp
+++ b/qmake/project.cpp
@@ -724,7 +724,7 @@ QMakeProject::isActiveConfig(const QString &x, bool regex, QMap<QString, QString
 	static char *buffer = NULL;
 	if(!buffer)
 	    buffer = (char *)malloc(1024);
-	int l = readlink(Option::mkfile::qmakespec, buffer, 1024);
+	int l = readlink(Option::mkfile::qmakespec, buffer, 1023);
 	if(l != -1) {
 	    buffer[l] = '\0';
 	    QString r = buffer;