DLL delay importing is a feature to load a DLL lazily, instead of
at program start-up time.
If the feature is turned on with the /delayload flag, the linker
resolves the delay-load helper function. All function pointer table
entries for the DLL are initially pointing to the helper function.
When called, the function loads and resolves the DLL symbols using
dlopen-ish Windows system calls and then write the reuslts to the
function pointer table. The helper function is in "delayimp.lib".
Note that this feature is not completely implemented yet. LLD
also needs to emit the table that's consumed by the delay-load
helper function. That'll be done in another patch.
llvm-svn: 218943
Previously the input file for the lib.exe command would be removed
as soon as the command exits, so we couldn't write a test to check
the file contents are correct.
This patch adds /lldmoduledeffile: option to retain a copy of the
temporary file at the given file path, so that you can see the file
if you want.
llvm-svn: 207727
Previously LLD would fail if /OPT:icf, /OPT:lbr or such are specified,
because these command line flags would be handled as unknown ones. We
rather want LLD to ignore these known but yet-to-be-implemented options
for now.
Added tests for the driver as well.
llvm-svn: 206863
/ignore:<number> is a linker option to disable warning specified by
the number. We ignore the option because it does not make sense for
LLD.
llvm-svn: 206636
Syntactically /SAFESEH is a boolean flag -- you can pass /SAFESEH or /SAFESEH:no.
The meaning of /SAFESEH is as follows.
- If /SAFESEH is specified, the linker will produce an executable with SEH table.
If any input files are not compatible with SEH, it's an error.
- If /SAFESEH:no is specified, the linker will not emit SEH table even if all
input files are compatible with SEH.
- If no option is specified, the linker emits SEH table if all input files are
compatible with SEH.
llvm-svn: 201895
Module-definition (.def) files are the file containing linker directives,
such as export symbols. Because link.exe supports the same features as command
line options, just as some Linker Script commands overlaps with command line
options, use of module-definition file is not really necessary. It provides
an alternative way to specify some linker options.
This patch implements EXPORTS directive. Other directives will be implemented
in the future.
llvm-svn: 198925
Command line argument separator on Windows is colon. We used to accept space
as a separator, but we removed most of the code for that. This patch is to
delete the remaining code.
llvm-svn: 198032
/DLLEXPORT is a command line option to export a symbol. __declspec(dllexport)
uses that to make the linker to export DLLExport'ed functions, by adding the
option to .drectve section.
This patch implements the parser of the command line option.
llvm-svn: 197122
/ALTERNATENAME is a rarely-used, undocumented command line option that is
needed to link LLD for release build. It seems that the option is for defining
an weak alias; /alternatename:foo=bar defines weak symbol "foo" for "bar".
If "foo" is defined in an input file, it'll be linked normally and the command
line option will have no effect. If it's not defined, "foo" will be handled
as an alias for "bar".
This patch implements the parser for the option. The actual weak alias handling
will be implemented in a separate patch.
llvm-svn: 196743
If /functionpadmin is specified, the linker is supposed to make room at the
beginning of each function, so that self-modifying program would easily
hotpatch existing functions. Since I'm not sure if this feature is really used,
I'll make LLD to ignore the option for now.
llvm-svn: 196363
/section command line option is to set/reset attributes of the Characteristics
field in the section header. You can set non-default values with this option.
You can make .data section executable with this, for example.
This patch implements the parser of the command line option. The code to use
the parsed values will be committed in a separate patch.
llvm-svn: 194133
I'm not sure if it is really an alias for /nodefaultlib, but I can say that
they are at least similar. Making it an alias would be better than ignoring it.
llvm-svn: 194131
msvcrt.lib contains "/disallowlib" command line option in its .drectve section.
I couldn't spot any documentation for the option. Ignore it for now so that we
can link the library without error.
llvm-svn: 194114
/merge:<from>=<to> option makes the linker to combine "from" section to "to"
section. This patch is to parse the option. The actual feature will be
implemented in a subsequent patch.
llvm-svn: 193454
/manifestfile:<path> specifies an alternative manifest file output path.
Default is "<output-path>.manifest" where <output-path> is the executable's
path.
llvm-svn: 193195
The manifest file is an XML file that conveys some information to the loader,
such as whether the executable needs to run as Administrator or not. This patch
is to parse command line option for manifest file.
Actual XML file generation will be done in a separate patch.
llvm-svn: 193141
/PDBALTPATH:<path> is an option to embed a different path for the PDB file to
the binary than the actual PDB file location. Because we don't support PDB
file, we'll just ignore the option for now.
llvm-svn: 191273
We used to support both Windows and Unix style command line options. In Windows
style, an option and its value are separated by ":" (colon). In Unix, separator
is a space. Accepting both styles were convenient, but we can no longer allow
Unix style because I found that can be ambiguous.
For example, /nodefaultlib option takes an optional argument. In Windows style
it's going to be something like "/nodefaultlib:foo". There's no ambiguity what
"foo" means. However, if the option is "/nodefaultlib foo", "foo" can be
interpreted either an optional argument for "/nodefaultlib" or an input file
"foo.obj". We should just stop accepting the non-standard command line style.
llvm-svn: 191247
These options are to enable DLL delay loading. If enabled, DLL is loaded
at run time by a helper routine when a function in the DLL is actually called
for the first time, instead of making the Windows loader to load all DLLs at
startup time. This should shorten startup delay if an executable have many
imported symbols.
The linker needs to create a "delayed import table" and link delayimp.lib in
which helper functions are defined to support the feature.
For now, we just ignore the options, so that the linker does not complain when
it sees these options. We want to support them in the future.
llvm-svn: 191232
/incremental is an option to enable incremental linking. We will eventually
want to implement the feature for better performance, but in the meantime,
we want to just ignore the option so that the linker does not output unknown
option error when it sees /incremental option.
llvm-svn: 191063
/errorReport is a command line option to let the linker to report internal
linker error information to Microsoft. For LLD that option doesn't make any
sense, so it just ignores the option.
llvm-svn: 191044
The compiler is allowed to add a linker option starting with -?<name> to
.drectve section. If the linker can interpret -<name>, it's processed as if
there's no question mark there. If not, such option is silently ignored.
This is a COFF's feature to allow the compiler to emit new linker options
while keeping compatibility with older linkers.
llvm-svn: 189897
This used to be handled automagically by the option parsing library,
but after LLVM r188314, we should handle it ourselves.
No functionality change, but adds a test.
llvm-svn: 188318
This patch does not change the behavior of LLD, but changes the output of the
help text. We want to show the help text with Windows style indicator rather
than Unix style indicator.
llvm-svn: 187544
Rui Ueyama