--- a/src/jsontestrunner/main.cpp.orig 2020-05-29 08:50:26.000000000 -0500 +++ b/src/jsontestrunner/main.cpp 2020-06-05 00:53:08.000000000 -0500 @@ -58,9 +58,11 @@ return ""; fseek(file, 0, SEEK_END); auto const size = ftell(file); + if (size == -1) + return ""; auto const usize = static_cast(size); fseek(file, 0, SEEK_SET); - auto buffer = new char[size + 1]; + auto buffer = new char[usize + 1]; buffer[size] = 0; Json::String text; if (fread(buffer, 1, usize, file) == usize)