Fix leak in case of fread failing

7 jobs for fix_potential_leak in 5 minutes (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #7462922
build

00:04:59

passed #7462927
build_android

00:00:53

passed #7462923
build_clang_libcpp

00:04:15

passed #7462926
build_clazy

00:04:32

passed #7462925
build_mingw64_fedora

00:03:09

passed #7462924
build_ubuntu_16_04

00:03:10

passed #7462921
clang_format

00:01:04