OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=21223
Crash type: Use-of-uninitialized-value
Crash state:
std::__1::vector<std::__1::vector<Sass::Extension, std::__1::allocator<Sass::Ext
Sass::Extender::extendCompound
Sass::Extender::extendComplex