Struct Invocation 

pub struct Invocation<'a> {

    pub inputs: &'a [Item],
    pub output: Option<&'a Path>,
    pub mode: LinkMode,
    pub search: &'a [PathBuf],
    pub no_startfiles: bool,
    pub no_defaultlibs: bool,
    pub no_builtins_lib: bool,
    pub builtins: Option<&'a Path>,
    pub export_dynamic: bool,
    pub strip: bool,
    pub gui: bool,
    pub unicode: bool,
    pub crt: Crt,
    pub reactor: bool,
    pub gcc: Option<&'a Path>,
    pub libgcc: Option<&'a Path>,
}

What the driver knows that the line needs, beyond the target and the sysroot.

A struct because most of it is empty in the common case, and because a function with nine positional parameters of which seven are usually a default is a function somebody calls wrong.

Fields

inputs: &'a [Item]

The objects and libraries, in the order they were written.

output: Option<&'a Path>

-o. Empty means the linker’s own default, which is what a caller testing a line wants.

mode: LinkMode

How the program is linked, which decides the start file and four of the flags.

search: &'a [PathBuf]

-L, in the order given. The user’s own, and they come before ours, because somebody who passed -L meant it to win.

no_startfiles: bool

-nostartfiles, which leaves crt1.o, crti.o and crtn.o off.

no_defaultlibs: bool

-nodefaultlibs, which leaves the libc and our runtime off.

no_builtins_lib: bool

-fno-builtins-lib, which leaves our own runtime off and keeps the libc.

It means something narrower here than it does on a native link. There it leaves ours off so that the machine’s libgcc answers for the wide arithmetic instead, and there is no libgcc in a generated sysroot, so here it leaves those names undefined. Which is what somebody passing it with a -l of their own is asking for, and the link says so by name if they are not.

builtins: Option<&'a Path>

Our own runtime archive for this target, if it is on the machine.

A path from the caller rather than a name this crate joins onto the sysroot, because it is the compiler’s own output for the target and not the platform’s, and a fetched sysroot will never hold it. The driver is what looks for it, in the -B prefixes and then beside the compiler, and None is what it says when there is none: the line goes without it and whatever wanted a wide divide is undefined. See crate::link::BUILTINS.

export_dynamic: bool

-rdynamic, which puts every symbol in the dynamic table so a program can look itself up.

strip: bool

-s, which drops the symbol table.

gui: bool

-mwindows, which makes a Windows program a GUI one: the windows subsystem, so no console is opened for it, and GDI and the common dialogs on the line the way gcc puts them there. Nothing on any other target.

unicode: bool

-municode, which starts a Windows program at wmain or wWinMain through crt2u.o instead of crt2.o. Nothing for a DLL or on any other target.

crt: Crt

-fms-runtime-lib=, which is /MT or /MD. Only a line for the MSVC environment reads it.

reactor: bool

-mexec-model=reactor, which makes a WASI module a reactor: crt1-reactor.o and the entry _initialize in place of crt1-command.o and _start. Nothing on any other target.

gcc: Option<&'a Path>

gcc’s runtime directory for a mingw-w64 target, when the tree the line is against has one.

That is a tree somebody named rather than one this compiler fetched, laid out the way MSYS2 lays out /ucrt64, with gcc’s own files under lib/gcc/<arch>-w64-mingw32/<version>. Its crtbegin.o goes after the start file and its crtend.o at the very end, the places gcc puts them, and the directory is searched after the tree’s lib so that a -lgcc finds the one beside them. LinkLine::mingw leaves both files off a fetched tree, which has no gcc in it, and nothing on any other target reads this. tamnd/rucc#2573.

libgcc: Option<&'a Path>

gcc’s libgcc.a for the target, which goes on after ours.

For what we have not written, which on a mingw-w64 target is the decimal floating point arithmetic, __bid_adddd3 and the rest of it. After ours so that ours answers for anything both have, and only what is still undefined by then is taken from it. The driver finds it in the named tree’s gcc directory or in a mingw-w64 gcc installed on this machine, and when there is neither a program using _Decimal64 fails to link by those names. tamnd/rucc#2145.

Trait Implementations

impl<'a> Clone for Invocation<'a>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'a> Debug for Invocation<'a>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a> Default for Invocation<'a>

fn default() -> Self

Returns the “default value” for a type.