libffcall-dev 2.2-1 (arm64 binary) in ubuntu focal

 ffcall is a collection of libraries which can be used to build
 foreign function call interfaces in embedded interpreters.
 .
 The main libffcall library consists of two parts:
 .
    avcall - calling C functions with variable arguments
 .
    callback - closures with variable arguments as first-class C functions
 .
 The avcall and callback modules are also provided as separate
 libraries, but those are deprecated and are installed only for backward
 compatibility.
 .
 Two other libraries are provided:
 .
    vacall - C functions accepting variable argument prototypes
    (non-reentrant variant of part of 'callback')
 .
    trampoline - closures as first-class C functions
    (non-reentrant variant of part of 'callback')
 .
 This package also includes documentation, in HTML format and as manual pages.