ffbuild: read library linker objects from a file

The linker command can exceed the maximum argument limit on MinGW,
especially for libavcodec.

The objects list is now stored in a file and passed to the linker.

.gitignore

@@ -1,5 +1,6 @@
 *.a
 *.o
+*.objs
 *.o.*
 *.d
 *.def

ffbuild/common.mak

@@ -214,7 +214,7 @@ $(TOOLOBJS): | tools
 
 OUTDIRS := $(OUTDIRS) $(dir $(OBJS) $(HOBJS) $(HOSTOBJS) $(SLIBOBJS) $(SHLIBOBJS) $(STLIBOBJS) $(TESTOBJS))
 
-CLEANSUFFIXES     = *.d *.gcda *.gcno *.h.c *.ho *.map *.o *.pc *.ptx *.ptx.gz *.ptx.c *.ver *.version *$(DEFAULT_X86ASMD).asm *~ *.ilk *.pdb
+CLEANSUFFIXES     = *.d *.gcda *.gcno *.h.c *.ho *.map *.o *.objs *.pc *.ptx *.ptx.gz *.ptx.c *.ver *.version *$(DEFAULT_X86ASMD).asm *~ *.ilk *.pdb
 LIBSUFFIXES       = *.a *.lib *.so *.so.* *.dylib *.dll *.def *.dll.a
 
 define RULES

ffbuild/library.mak

@@ -35,8 +35,10 @@ OBJS += $(SHLIBOBJS)
 endif
 $(SUBDIR)$(LIBNAME): $(OBJS) $(STLIBOBJS)
 	$(RM) $@
-	$(AR) $(ARFLAGS) $(AR_O) $^
+	$(Q)echo $^ > $@.objs
+	$(AR) $(ARFLAGS) $(AR_O) @$@.objs
 	$(RANLIB) $@
+	-$(RM) $@.objs
 
 install-headers: install-lib$(NAME)-headers install-lib$(NAME)-pkgconfig
 
@@ -66,8 +68,10 @@ $(SUBDIR)$(SLIBNAME): $(SUBDIR)$(SLIBNAME_WITH_MAJOR)
 
 $(SUBDIR)$(SLIBNAME_WITH_MAJOR): $(OBJS) $(SHLIBOBJS) $(SLIBOBJS) $(SUBDIR)lib$(NAME).ver
 	$(SLIB_CREATE_DEF_CMD)
-	$$(LD) $(SHFLAGS) $(LDFLAGS) $(LDSOFLAGS) $$(LD_O) $$(filter %.o,$$^) $(FFEXTRALIBS)
+	$(Q)echo $$(filter %.o,$$^) > $$@.objs
+	$$(LD) $(SHFLAGS) $(LDFLAGS) $(LDSOFLAGS) $$(LD_O) @$$@.objs $(FFEXTRALIBS)
 	$(SLIB_EXTRA_CMD)
+	-$(RM) $$@.objs
 
 ifdef SUBDIR
 $(SUBDIR)$(SLIBNAME_WITH_MAJOR): $(DEP_LIBS)