#./assemble_vintf --help

assemble_vintf: Checks if a given manifest / matrix file is valid and 
    fill in build-time flags into the given file.
assemble_vintf -h
               Display this help text.
assemble_vintf -i <input file>[:<input file>[...]] [-o <output file>] [-m]
               [-c [<check file>]]
               Fill in build-time flags into the given file.
    -i <input file>[:<input file>[...]]
               A list of input files. Format is automatically detected for the
               first file, and the remaining files must have the same format.
               Files other than the first file should only have <hal> defined;
               other entries are ignored. Argument may also be specified
               multiple times.
    -o <output file>
               Optional output file. If not specified, write to stdout.
    -m
               a compatible compatibility matrix is
               generated instead; for example, given a device manifest,
               a framework compatibility matrix is generated. This flag
               is ignored when input is a compatibility matrix.
    -c [<check file>]
               The path of the "check file"; for example, this is the path
               of the device manifest for framework compatibility matrix.
               After writing the output file, the program checks against
               the "check file", depending on environment variables.
               - PRODUCT_ENFORCE_VINTF_MANIFEST=true: check compatibility
               If any check fails, an error message is written to stderr.
               Return 1.
    --kernel=<version>:<android-base.config>[:<android-base-arch.config>[...]]
               Add a kernel entry to framework compatibility matrix or device
               manifest. Ignored for other input format.
               There can be any number of --kernel for framework compatibility
               matrix, but at most one --kernel and at most one config file for
               device manifest.
               <version> has format: 3.18.0
               <android-base.config> is the location of android-base.config
               <android-base-arch.config> is the location of an optional
               arch-specific config fragment, more than one may be specified
    -l, --hals-only
               Output has only <hal> entries. Cannot be used with -n.
    -n, --no-hals
               Output has no <hal> entries (but all other entries).
               Cannot be used with -l.
    --no-kernel-requirements
               Output has no <config> entries in <kernel>, and kernel minor
               version is set to zero. (For example, 3.18.0).