Assertion failure in reset_freetype_face_char_size

thread 'main' panicked at 'assertion failed: `(left == right)`
  left: `23`,
 right: `0`', /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/loaders/freetype.rs:1148:9
stack backtrace:
   0:     0x55f70db7e108 - backtrace::backtrace::libunwind::trace::hccf7fcb8c3efd6c9
                               at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.40/src/backtrace/libunwind.rs:88
   1:     0x55f70db7e108 - backtrace::backtrace::trace_unsynchronized::hdc571c1189c74524
                               at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.40/src/backtrace/mod.rs:66
   2:     0x55f70db7e108 - std::sys_common::backtrace::_print_fmt::ha340006a6f654784
                               at src/libstd/sys_common/backtrace.rs:77
   3:     0x55f70db7e108 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h1edb2343f5ef9fa1
                               at src/libstd/sys_common/backtrace.rs:59
   4:     0x55f70dba4f3c - core::fmt::write::h5daa3012650ec288
                               at src/libcore/fmt/mod.rs:1052
   5:     0x55f70db7aa97 - std::io::Write::write_fmt::h1393c2aa40b28ea2
                               at src/libstd/io/mod.rs:1428
   6:     0x55f70db80855 - std::sys_common::backtrace::_print::h0e150e7c3dc63729
                               at src/libstd/sys_common/backtrace.rs:62
   7:     0x55f70db80855 - std::sys_common::backtrace::print::h9d3d00a79f010614
                               at src/libstd/sys_common/backtrace.rs:49
   8:     0x55f70db80855 - std::panicking::default_hook::{{closure}}::hd61a1ad6b6137da7
                               at src/libstd/panicking.rs:204
   9:     0x55f70db80596 - std::panicking::default_hook::h21ddd7c2447fb722
                               at src/libstd/panicking.rs:224
  10:     0x55f70db80eb2 - std::panicking::rust_panic_with_hook::he2460faa61118cbf
                               at src/libstd/panicking.rs:470
  11:     0x55f70db80a9b - rust_begin_unwind
                               at src/libstd/panicking.rs:378
  12:     0x55f70db80a0b - std::panicking::begin_panic_fmt::he0dc876ab7e2bfae
                               at src/libstd/panicking.rs:332
  13:     0x55f70d52a813 - font_kit::loaders::freetype::reset_freetype_face_char_size::h0391068e315091b8
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/loaders/freetype.rs:1148
  14:     0x55f70d52a813 - font_kit::loaders::freetype::setup_freetype_face::h7ee5c2353b987cd5
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/loaders/freetype.rs:1141
  15:     0x55f70d52a813 - font_kit::loaders::freetype::Font::from_bytes::{{closure}}::he1f6033884b0f4f8
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/loaders/freetype.rs:146
  16:     0x55f70d52a813 - std::thread::local::LocalKey<T>::try_with::h2ee65874e39f60da
                               at /rustc/442ae7f04026c215a03b155eaaf9cde8bb5cf02a/src/libstd/thread/local.rs:262
  17:     0x55f70d52a813 - std::thread::local::LocalKey<T>::with::hde6561fef2ba6181
                               at /rustc/442ae7f04026c215a03b155eaaf9cde8bb5cf02a/src/libstd/thread/local.rs:239
  18:     0x55f70d528830 - font_kit::loaders::freetype::Font::from_bytes::h2983f62baec3d999
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/loaders/freetype.rs:133
  19:     0x55f70d528830 - font_kit::loaders::freetype::Font::from_file::h8960a8fd369797e9
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/loaders/freetype.rs:163
  20:     0x55f70d4af4d1 - <font_kit::loaders::freetype::Font as font_kit::loader::Loader>::from_file::ha3ee8c5920c512ba
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/loaders/freetype.rs:997
  21:     0x55f70d4af4d1 - font_kit::loader::Loader::from_path::hd9c3d70da2e89a25
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/loader.rs:90
  22:     0x55f70d4af4d1 - font_kit::loader::Loader::from_handle::h4b5ce9e5391bfb1e
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/loader.rs:107
  23:     0x55f70d4d00c9 - font_kit::loaders::freetype::Font::from_handle::had441b0afe9cbe24
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/loaders/freetype.rs:206
  24:     0x55f70d4d00c9 - font_kit::source::Source::select_descriptions_in_family::hc9e7d10095fe80ff
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/source.rs:146
  25:     0x55f70d522384 - font_kit::source::Source::select_best_match::h7e292a7dcba443d2
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/source.rs:130
  26:     0x55f70d522384 - font_kit::sources::fontconfig::FontconfigSource::select_best_match::h897dbc4d8c1f8436
                               at /home/shui/.cargo/registry/src/github.com-1ecc6299db9ec823/font-kit-0.5.0/src/sources/fontconfig.rs:206

Start by inspecting loaders/freetype.rs around reset_freetype_face_char_size at line 1148 and its call from setup_freetype_face. Reproduce the reported panic through Font::from_file or FontconfigSource::select_best_match, then determine what behavior should replace the assertion; done means the reported font-loading path no longer panics.