[4/5] configure: Use dllexport/dllimport for data symbols across DLLs with mingw

diff mbox

This avoids having to use pseudo relocations.

The version script used for exporting functions is skipped as soon
as the set of object files contains symbols marked with dllexport,
therefore we need to use makedef to produce the full list of symbols
to be exported.
---
Improved commit message, renamed makefile variables slightly.
---
 configure             | 11 +++++++++--
 libavcodec/internal.h |  2 +-
 2 files changed, 10 insertions(+), 3 deletions(-)

On Fri, Aug 25, 2017 at 10:46:43AM +0300, Martin Storsjö wrote:
> --- a/configure
> +++ b/configure
> @@ -4032,6 +4032,10 @@ case $target_os in
>          elif enabled arm; then
>              LIBTARGET=arm-wince
>          fi
> +        if enabled shared; then
> +            # Cannot build both shared and static libs when using dllexport.
> +            disable static
> +        fi
>          check_ldflags -Wl,--nxcompat
>          check_ldflags -Wl,--dynamicbase
>          shlibdir_default="$bindir_default"
> @@ -4039,12 +4043,13 @@ case $target_os in
>          SLIBSUF=".dll"
>          SLIBNAME_WITH_VERSION='$(SLIBPREF)$(NAME)-$(LIBVERSION)$(SLIBSUF)'
>          SLIBNAME_WITH_MAJOR='$(SLIBPREF)$(NAME)-$(LIBMAJOR)$(SLIBSUF)'
> -        SLIB_EXTRA_CMD=-'sed -e "s/ @[^ ]*//" $$(@:$(SLIBSUF)=.orig.def) > $$(@:$(SLIBSUF)=.def); $(DLLTOOL) -m $(LIBTARGET) -d $$(@:$(SLIBSUF)=.def) -l $(SUBDIR)$(SLIBNAME:$(SLIBSUF)=.lib) -D $(SLIBNAME_WITH_MAJOR)'
> +        SLIB_EXTRA_CMD=-'$(DLLTOOL) -m $(LIBTARGET) -d $$(@:$(SLIBSUF)=.def) -l $(SUBDIR)$(SLIBNAME:$(SLIBSUF)=.lib) -D $(SLIBNAME_WITH_MAJOR)'
>          SLIB_INSTALL_NAME='$(SLIBNAME_WITH_MAJOR)'
>          SLIB_INSTALL_LINKS=
>          SLIB_INSTALL_EXTRA_SHLIB='$(SLIBNAME:$(SLIBSUF)=.lib)'
>          SLIB_INSTALL_EXTRA_LIB='lib$(SLIBNAME:$(SLIBSUF)=.dll.a) $(SLIBNAME_WITH_MAJOR:$(SLIBSUF)=.def)'
> -        SHFLAGS='-shared -Wl,--output-def,$$(@:$(SLIBSUF)=.orig.def) -Wl,--out-implib,$(SUBDIR)lib$(SLIBNAME:$(SLIBSUF)=.dll.a) -Wl,--enable-runtime-pseudo-reloc -Wl,--enable-auto-image-base'
> +        SLIB_CREATE_DEF_CMD='ARCH="$(ARCH)" AR="$(AR_CMD)" NM="$(NM_CMD)" $(SRC_PATH)/compat/windows/makedef $(SUBDIR)lib$(NAME).ver $(OBJS) > $$(@:$(SLIBSUF)=.def)'
> +        SHFLAGS='-shared -Wl,--out-implib,$(SUBDIR)lib$(SLIBNAME:$(SLIBSUF)=.dll.a) -Wl,--enable-auto-image-base $$(@:$(SLIBSUF)=.def)'
>          enabled x86_64 && objformat="win64" || objformat="win32"
>          dlltool="${cross_prefix}dlltool"
>          ranlib=:
> @@ -5438,6 +5443,8 @@ DEPX86ASMFLAGS=\$(X86ASMFLAGS)
>  AR=$ar
>  ARFLAGS=$arflags
>  AR_O=$ar_o
> +AR_CMD=$ar
> +NM_CMD=$nm

You need these extra indirections over the AR and NM variables in the
Makefile because ... ?

Diego

On Sun, 3 Sep 2017, Diego Biurrun wrote:

> On Fri, Aug 25, 2017 at 10:46:43AM +0300, Martin Storsjö wrote:
>> --- a/configure
>> +++ b/configure
>> @@ -4032,6 +4032,10 @@ case $target_os in
>>          elif enabled arm; then
>>              LIBTARGET=arm-wince
>>          fi
>> +        if enabled shared; then
>> +            # Cannot build both shared and static libs when using dllexport.
>> +            disable static
>> +        fi
>>          check_ldflags -Wl,--nxcompat
>>          check_ldflags -Wl,--dynamicbase
>>          shlibdir_default="$bindir_default"
>> @@ -4039,12 +4043,13 @@ case $target_os in
>>          SLIBSUF=".dll"
>>          SLIBNAME_WITH_VERSION='$(SLIBPREF)$(NAME)-$(LIBVERSION)$(SLIBSUF)'
>>          SLIBNAME_WITH_MAJOR='$(SLIBPREF)$(NAME)-$(LIBMAJOR)$(SLIBSUF)'
>> -        SLIB_EXTRA_CMD=-'sed -e "s/ @[^ ]*//" $$(@:$(SLIBSUF)=.orig.def) > $$(@:$(SLIBSUF)=.def); $(DLLTOOL) -m $(LIBTARGET) -d $$(@:$(SLIBSUF)=.def) -l $(SUBDIR)$(SLIBNAME:$(SLIBSUF)=.lib) -D $(SLIBNAME_WITH_MAJOR)'
>> +        SLIB_EXTRA_CMD=-'$(DLLTOOL) -m $(LIBTARGET) -d $$(@:$(SLIBSUF)=.def) -l $(SUBDIR)$(SLIBNAME:$(SLIBSUF)=.lib) -D $(SLIBNAME_WITH_MAJOR)'
>>          SLIB_INSTALL_NAME='$(SLIBNAME_WITH_MAJOR)'
>>          SLIB_INSTALL_LINKS=
>>          SLIB_INSTALL_EXTRA_SHLIB='$(SLIBNAME:$(SLIBSUF)=.lib)'
>>          SLIB_INSTALL_EXTRA_LIB='lib$(SLIBNAME:$(SLIBSUF)=.dll.a) $(SLIBNAME_WITH_MAJOR:$(SLIBSUF)=.def)'
>> -        SHFLAGS='-shared -Wl,--output-def,$$(@:$(SLIBSUF)=.orig.def) -Wl,--out-implib,$(SUBDIR)lib$(SLIBNAME:$(SLIBSUF)=.dll.a) -Wl,--enable-runtime-pseudo-reloc -Wl,--enable-auto-image-base'
>> +        SLIB_CREATE_DEF_CMD='ARCH="$(ARCH)" AR="$(AR_CMD)" NM="$(NM_CMD)" $(SRC_PATH)/compat/windows/makedef $(SUBDIR)lib$(NAME).ver $(OBJS) > $$(@:$(SLIBSUF)=.def)'
>> +        SHFLAGS='-shared -Wl,--out-implib,$(SUBDIR)lib$(SLIBNAME:$(SLIBSUF)=.dll.a) -Wl,--enable-auto-image-base $$(@:$(SLIBSUF)=.def)'
>>          enabled x86_64 && objformat="win64" || objformat="win32"
>>          dlltool="${cross_prefix}dlltool"
>>          ranlib=:
>> @@ -5438,6 +5443,8 @@ DEPX86ASMFLAGS=\$(X86ASMFLAGS)
>>  AR=$ar
>>  ARFLAGS=$arflags
>>  AR_O=$ar_o
>> +AR_CMD=$ar
>> +NM_CMD=$nm
>
> You need these extra indirections over the AR and NM variables in the
> Makefile because ... ?

In quiet builds (the default), AR gets prepened with @printf stuff, which 
doesn't work when this is passed onto a shellscript that it supposed to 
execute it. And NM isn't exported into the makefiles at all yet (it's only 
used during configure so far) - I opted to add _CMD for consistency since 
it's supposed to be the raw command just like for AR_CMD, not something 
with potential extra makefile stuff in it.

// Martin