diff options
Diffstat (limited to 'ld/ld.texinfo')
| -rw-r--r-- | ld/ld.texinfo | 119 |
1 files changed, 117 insertions, 2 deletions
diff --git a/ld/ld.texinfo b/ld/ld.texinfo index 8d85f95..c7fd318 100644 --- a/ld/ld.texinfo +++ b/ld/ld.texinfo @@ -43,6 +43,7 @@ @set C54X @set V850 @set VAX +@set WIN32 @end ifset @c man end @@ -145,6 +146,9 @@ section entitled "GNU Free Documentation License". @ifset TICOFF * TI COFF:: ld and the TI COFF @end ifset +@ifset WIN32 +* Win32:: ld and WIN32 (cygwin/mingw) +@end ifset @end ifclear @ifclear SingleFormat * BFD:: BFD @@ -894,6 +898,18 @@ Using this option has a significant performance cost. It is best to use it only when there are unavoidable circular references between two or more archives. +@kindex --accept-unknown-input-format +@kindex --no-accept-unknown-input-format +@item --accept-unknown-input-format +@itemx --no-accept-unknown-input-format +Tells the linker to accept input files whoes format cannot be +recognised. The assumption is that the user knows what they are doing +and deliberately wants to link in these unknown format input files. +This was the default behaviour of the linker, before release 2.14. +The default behaviour from release 2.14 onwards is to reject such +input files, and so the @samp{--accept-unknown-input-format} option +has been added to restore the old behaviour. + @kindex -assert @var{keyword} @item -assert @var{keyword} This option is ignored for SunOS compatibility. @@ -1789,8 +1805,8 @@ uwin, pw, etc. For instance, cygwin DLLs typically use @item --enable-auto-import Do sophisticated linking of @code{_symbol} to @code{__imp__symbol} for DATA imports from DLLs, and create the necessary thunking symbols when -building the DLLs with those DATA exports. This generally will 'just -work' -- but sometimes you may see this message: +building the import libraries with those DATA exports. This generally +will 'just work' -- but sometimes you may see this message: "variable '<var>' can't be auto-imported. Please read the documentation for ld's @code{--enable-auto-import} for details." @@ -4380,6 +4396,9 @@ functionality are not listed. @ifset TICOFF * TI COFF:: @command{ld} and TI COFF @end ifset +@ifset WIN32 +* WIN32:: @command{ld} and WIN32 (cygwin/mingw) +@end ifset @end menu @end ifset @@ -4421,6 +4440,102 @@ top page of memory). @end ifclear @end ifset +@ifset WIN32 +@ifclear GENERIC +@raisesections +@end ifclear + +@node WIN32 +@section @command{ld} and WIN32 (cygwin/mingw) + +This section describes some of the win32 specific @command{ld} issues. + +@table @emph +@cindex import libraries +@item import libraries +The standard Windows linker creates and uses so called import +libraries, which contains information for linking to dll's. They are +regular static archives and could be handled as any other static +archive. The cygwin and mingw ports of @command{ld} has specific +support for creating such libraries provided with the +@samp{--out-implib} command line option. + +@cindex automatic data imports +@item automatic data imports +The standard Windows dll format supports data imports from dlls only +by adding special decorations (dllimport/dllexport), which lets the +compiler produce specific assembler instructions to deal with this +issue. This increase the needed porting efforts, especially for big +c++ libraries and applications. The auto-import feature, which was +initially provided by Paul Sokolovsky, allows this decoration to be +skipped, archiving a behavior more like @command{ld} on other +platforms. This feature is enabled with the @samp{--enable-auto-import} +command line option. + +@cindex direct linking to a dll +@item direct linking to a dll +The cygwin/mingw ports of @command{ld} support the direct linking, +including data symbols, to a dll without the usage of any import +libraries. Using this feature can save a lot of linking time and +memory, especially in case of bigger libraries or applications. This +is because bigger libraries can have very large import libraries. (The +author has seen import libraries about 10 MB size). + +Linking directly to a dll can done with the standard command line +options @samp{-L} and @samp{-l}. This is because @command{ld} has +built in support for several dll names, as shown below. In this list +@samp{xxx} means the basic library name like "png" for the png +library: + +@example +libxxx.dll.a +xxx.dll.a +libxxx.a +cygxxx.dll +libxxx.dll +xxx.dll +@end example + +The generic cygwin/mingw path layout uses a @samp{bin} directory for +applications and dll's and a @samp{lib} directory for the import +libraries. + +@example +bin/ + cygxxx.dll +lib/ + libxxx.dll.a (in case of dll's) + libxxx.a (in case of static archive) +@end example + +Linking to a dll can be done by two ways: + +1. Use the dll directly by adding the @samp{bin} path to the link line +@example +gcc -Wl,-verbose -o a.exe -L../bin/ -lxxx +@end example + +2. Create a symbolic link from the dll to a file in the @samp{lib} +directory according to the above mentioned search pattern. This +should be used to avoid unwanted changes in the tools needed for +making the app/dll. + +@example +ln -s bin/cygxxx.dll lib/[cyg|lib|]xxx.dll[.a] +@end example + +Then you can link without any make environment changes. + +@example +gcc -Wl,-verbose -o a.exe -L../lib/ -lxxx +@end example +@end table + +@ifclear GENERIC +@lowersections +@end ifclear +@end ifset + @ifclear GENERIC @ifset Hitachi @c This stuff is pointless to say unless you're especially concerned |