https://bugs.gentoo.org/779445

commit ed1030d9b6a98e06aa293d18c49da18169918b8b
Author: orbea <orbea@riseup.net>
Date:   Tue Mar 30 18:57:37 2021 -0700

    Fix the build with parallel make and slibtool.
    
    There is no dependency on the $(OBJECTS) files on the 'build'
    directory which causes slibtool to fail when the directory
    does not yet exist. GNU libtool avoids this by being slower
    than mkdir(1).

diff --git a/Makefile.in b/Makefile.in
index ab51035..90940d4 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -51,7 +51,7 @@ LT_RELEASE  = @LT_RELEASE@
 LT_REVISION = @LT_REVISION@
 LT_LDFLAGS  = -no-undefined -rpath $(DESTDIR)$(libdir) -release $(LT_RELEASE) -version-info $(LT_CURRENT):$(LT_REVISION):$(LT_AGE)
 
-all: $(srcdir)/configure Makefile $(objects) $(objects)/$(TARGET) $(objects)/$(SDLMAIN_TARGET)
+all: $(srcdir)/configure Makefile $(objects)/$(TARGET) $(objects)/$(SDLMAIN_TARGET)
 
 $(srcdir)/configure: $(srcdir)/configure.in
 	@echo "Warning, configure.in is out of date"
@@ -61,8 +61,9 @@ $(srcdir)/configure: $(srcdir)/configure.in
 Makefile: $(srcdir)/Makefile.in
 	$(SHELL) config.status $@
 
-$(objects):
-	$(SHELL) $(auxdir)/mkinstalldirs $@
+$(objects)/.created:
+	$(SHELL) $(auxdir)/mkinstalldirs $(objects)
+	touch $@
 
 .PHONY: all depend install install-bin install-hdrs install-lib install-data install-man uninstall uninstall-bin uninstall-hdrs uninstall-lib uninstall-data uninstall-man clean distclean dist
 depend:
@@ -71,6 +72,8 @@ depend:
 
 include $(depend)
 
+$(OBJECTS) $(SDLMAIN_OBJECTS): $(objects)/.created
+
 $(objects)/$(TARGET): $(OBJECTS)
 	$(LIBTOOL) --mode=link $(CC) -o $@ $^ $(LDFLAGS) $(EXTRA_LDFLAGS) $(LT_LDFLAGS)
 
@@ -88,7 +91,7 @@ install-hdrs:
 	    $(INSTALL) -m 644 $(srcdir)/include/$$file $(DESTDIR)$(includedir)/SDL/$$file; \
 	done
 	$(INSTALL) -m 644 include/SDL_config.h $(DESTDIR)$(includedir)/SDL/SDL_config.h
-install-lib: $(objects) $(objects)/$(TARGET) $(objects)/$(SDLMAIN_TARGET)
+install-lib: $(objects)/$(TARGET) $(objects)/$(SDLMAIN_TARGET)
 	$(SHELL) $(auxdir)/mkinstalldirs $(DESTDIR)$(libdir)
 	$(LIBTOOL) --mode=install $(INSTALL) $(objects)/$(TARGET) $(DESTDIR)$(libdir)/$(TARGET)
 	$(LIBTOOL) --mode=install $(INSTALL) $(objects)/$(SDLMAIN_TARGET) $(DESTDIR)$(libdir)/$(SDLMAIN_TARGET)