llvm-ar [-]{dmpqrstx}[abcDilLNoOPsSTuUvV] [relpos] [count]
archive [files…]
The llvm-ar command is similar to the common Unix utility,
ar. It archives several files, such as objects and LLVM bitcode files
into a single archive library that can be linked into a program. However,
the archive can contain any kind of file. By default, llvm-ar
generates a symbol table that makes linking faster because only the symbol
table needs to be consulted, not each individual file member of the
archive.
The llvm-ar command can be used to read archive
files in SVR4, GNU, BSD , Big Archive, and Darwin format, and write
in the GNU, BSD, Big Archive, and Darwin style archive files. If an SVR4
format archive is used with the r (replace), d (delete),
m (move) or q (quick update) operations, the archive will be
reconstructed in the format defined by --format.
Here’s where llvm-ar departs from previous ar
implementations:
The following option is not supported
[f] - truncate inserted filenames
The following options are ignored for compatibility
–plugin=<string> - load a plugin which adds
support for other file formats
[l] - ignored in ar
Symbol Table
Since llvm-ar supports bitcode files, the symbol
table it creates includes both native and bitcode symbols.
Deterministic Archives
By default, llvm-ar always uses zero for
timestamps and UIDs/GIDs to write archives in a deterministic mode. This is
equivalent to the D modifier being enabled by default. If you wish to
maintain compatibility with other ar implementations, you can pass the
U modifier to write actual timestamps and UIDs/GIDs.
Windows Paths
When on Windows llvm-ar treats the names of
archived files in the same case sensitive manner as the operating
system. When on a non-Windows machine llvm-ar does not consider
character case.
llvm-ar operations are compatible with other ar
implementations. However, there are a few modifiers (L) that are not
found in other ar implementations. The options for llvm-ar
specify a single basic Operation to perform on the archive, a variety of
Modifiers for that Operation, the name of the archive file, and an optional
list of file names. If the files option is not specified, it
generally means either “none” or “all” members,
depending on the operation. The Options, Operations and Modifiers are
explained in the sections below.
The minimal set of options is at least one operator and the name
of the archive.
- d [NT]
- Delete files from the archive. The N and T modifiers
apply to this operation. The files options specify which members
should be removed from the archive. It is not an error if a specified file
does not appear in the archive. If no files are specified, the
archive is not modified.
- m [abi]
- Move files from one location in the archive to another. The
a, b, and i modifiers apply to this operation. The
files will all be moved to the location given by the modifiers. If
no modifiers are used, the files will be moved to the end of the archive.
If no files are specified, the archive is not modified.
- p [v]
- Print files to the standard output stream. If no files are
specified, the entire archive is printed. With the v
modifier, llvm-ar also prints out the name of the file being
output. Printing binary files is ill-advised as they might confuse your
terminal settings. The p operation never modifies the archive.
- q [LT]
- Quickly append files to the end of the archive without removing
duplicates. If no files are specified, the archive is not modified.
The behavior when appending one archive to another depends upon whether
the L and T modifiers are used:
- Appending a regular archive to a regular archive will append the archive
file. If the L modifier is specified the members will be appended
instead.
- Appending a regular archive to a thin archive requires the T
modifier and will append the archive file. The L modifier is not
supported.
- Appending a thin archive to a regular archive will append the archive
file. If the L modifier is specified the members will be appended
instead.
- Appending a thin archive to a thin archive will always quick append its
members.
- r [abTu]
- Replace existing files or insert them at the end of the
archive if they do not exist. The a, b, T and
u modifiers apply to this operation. If no files are
specified, the archive is not modified.
t[v] .. option:: t [vO]
Print the table of contents. Without any modifiers, this
operation just prints the names of the members to the standard output stream.
With the v modifier, llvm-ar also prints out the file type
(B=bitcode, S=symbol table, blank=regular file), the permission mode, the
owner and group, are ignored when extracting files and set to
placeholder values when adding size, and the date. With the O modifier,
display member offsets. If any files are specified, the listing is only
for those files. If no files are specified, the table of contents for
the whole archive is printed.
- V
- A synonym for the --version option.
- x [oP]
- Extract archive members back to files. The o modifier
applies to this operation. This operation retrieves the indicated
files from the archive and writes them back to the operating
system’s file system. If no files are specified, the entire
archive is extracted.
The modifiers below are specific to certain operations. See the
Operations section to determine which modifiers are applicable to which
operations.
- a
- When inserting or moving member files, this option specifies the
destination of the new files as being after the relpos member. If
relpos is not found, the files are placed at the end of the
archive. relpos cannot be consumed without either a,
b or i.
- b
- When inserting or moving member files, this option specifies the
destination of the new files as being before the relpos member. If
relpos is not found, the files are placed at the end of the
archive. relpos cannot be consumed without either a,
b or i. This modifier is identical to the i
modifier.
- i
- A synonym for the b option.
- L
- When quick appending an archive, instead quick append its members.
This is a feature for llvm-ar that is not found in gnu-ar.
- N
- When extracting or deleting a member that shares its name with another
member, the count parameter allows you to supply a positive whole
number that selects the instance of the given name, with “1”
indicating the first instance. If N is not specified the first
member of that name will be selected. If count is not supplied, the
operation fails.*count* cannot be
- o
- When extracting files, use the modification times of any files as
they appear in the archive. By default files extracted from
the archive use the time of extraction.
- O
- Display member offsets inside the archive.
- T
- Alias for --thin. In many ar implementations T has a
different meaning, as specified by X/Open System interface.
- v
- When printing files or the archive table of contents, this
modifier instructs llvm-ar to include additional information in the
output.
The modifiers below may be applied to any operation.
- c
- For the r (replace)and q (quick update) operations,
llvm-ar will always create the archive if it doesn’t exist.
Normally, llvm-ar will print a warning message indicating that the
archive is being created. Using this modifier turns off that
warning.
- D
- Use zero for timestamps and UIDs/GIDs. This is set by default.
- P
- Use full paths when matching member names rather than just the file name.
This can be useful when manipulating an archive generated by
another archiver, as some allow paths as member names. This is the default
behavior for thin archives.
- s
- This modifier requests that an archive index (or symbol table) be added to
the archive, as if using ranlib. The symbol table will contain all
the externally visible functions and global variables defined by all the
bitcode files in the archive. By default llvm-ar generates symbol
tables in archives. This can also be used as an operation.
- S
- This modifier is the opposite of the s modifier. It instructs
llvm-ar to not build the symbol table. If both s and
S are used, the last modifier to occur in the options will
prevail.
- u
- Only update archive members with files that have more recent
timestamps.
- U
- Use actual timestamps and UIDs/GIDs.
- --format=<type>
- This option allows for default, gnu, darwin or bsd <type> to
be selected. When creating an archive, <type> will
default to that of the host machine.
- -h, --help
- Print a summary of command-line options and their meanings.
- -M
- This option allows for MRI scripts to be read through the standard input
stream. No other options are compatible with this option.
- --output=<dir>
- Specify a directory where archive members should be extracted to. By
default the current working directory is used.
- --thin
- When creating or modifying an archive, this option specifies that the
archive will be thin. By default, archives are not created as thin
archives and when modifying a thin archive, it will be converted to a
regular archive.
- --version
- Display the version of the llvm-ar executable.
- -X mode
- Specifies the type of object file llvm-ar will recognise. The mode
must be one of the following:
- 32
- Process only 32-bit object files.
- 64
- Process only 64-bit object files.
- 32_64
- Process both 32-bit and 64-bit object files.
- any
- Process all object files.
The default is to process 32-bit object files (ignore 64-bit
objects). The mode can also be set with the OBJECT_MODE environment
variable. For example, OBJECT_MODE=64 causes ar to process any 64-bit
objects and ignore 32-bit objects. The -X flag overrides the OBJECT_MODE
variable.
- @<FILE>
- Read command-line options and commands from response file
<FILE>.
llvm-ar understands a subset of the MRI scripting interface
commonly supported by archivers following in the ar tradition. An MRI script
contains a sequence of commands to be executed by the archiver. The
-M option allows for an MRI script to be passed to llvm-ar
through the standard input stream.
Note that llvm-ar has known limitations regarding the use
of MRI scripts:
- Each script can only create one archive.
- Existing archives can not be modified.
Each command begins with the command’s name and must appear
on its own line. Some commands have arguments, which must be separated from
the name by whitespace. An MRI script should begin with either a
CREATE or CREATETHIN command and will typically end with a
SAVE command. Any text after either ‘*’ or
‘;’ is treated as a comment.
- CREATE
archive
- Begin creation of a regular archive with the specified name. Subsequent
commands act upon this archive.
- CREATETHIN
archive
- Begin creation of a thin archive with the specified name. Subsequent
commands act upon this archive.
- DELETE
<file>
- Delete the member of the current archive whose file name, excluding
directory components, matches <file>.
- SAVE
- Write the current archive to the path specified in the previous
CREATE/CREATETHIN command.
- END
- Ends the MRI script (optional).
If llvm-ar succeeds, it will exit with 0. Otherwise, if an
error occurs, it will exit with a non-zero value.
Maintained by the LLVM Team (https://llvm.org/).