diff --git a/games-fps/assaultcube/assaultcube-1.3.0.2.ebuild b/games-fps/assaultcube/assaultcube-1.3.0.2-r1.ebuild
similarity index 94%
rename from games-fps/assaultcube/assaultcube-1.3.0.2.ebuild
rename to games-fps/assaultcube/assaultcube-1.3.0.2-r1.ebuild
index 25001c0611..0301e81c04 100644
--- a/games-fps/assaultcube/assaultcube-1.3.0.2.ebuild
+++ b/games-fps/assaultcube/assaultcube-1.3.0.2-r1.ebuild
@@ -1,4 +1,4 @@
-# Copyright 1999-2022 Gentoo Authors
+# Copyright 1999-2024 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 EAPI=8
@@ -20,16 +20,18 @@ RDEPEND="
 	media-libs/libsdl2[opengl]
 	media-libs/sdl2-image[jpeg,png]
 	x11-libs/libX11
+	media-libs/libglvnd[X]
 	media-libs/libogg
 	media-libs/libvorbis
 	media-libs/openal
 "
 DEPEND="${RDEPEND}"
-BDEPEND="sys-devel/clang"
 PATCHES=(
 	"${FILESDIR}/${PN}-1.3.0.2-respect-ldflags.patch"
 	# a script which checks for required libs and certain parts of the game
 	"${FILESDIR}/${PN}-1.3.0.2-fix-checkinstall.patch"
+	# bug #921915
+	"${FILESDIR}/${PN}-1.3.0.2-unset-variables.patch"
 	"${FILESDIR}/0001-Fix-unnecessary-rebuild-on-make-install.patch"
 	"${FILESDIR}/0002-Don-t-configure-libenet-in-Makefile.patch"
 )
diff --git a/games-fps/assaultcube/files/assaultcube-1.3.0.2-unset-variables.patch b/games-fps/assaultcube/files/assaultcube-1.3.0.2-unset-variables.patch
new file mode 100644
index 0000000000..1bc54b38c6
--- /dev/null
+++ b/games-fps/assaultcube/files/assaultcube-1.3.0.2-unset-variables.patch
@@ -0,0 +1,32 @@
+Respect user preferences during the build and fix the Clang build by
+disabling PCH.
+https://bugs.gentoo.org/921915
+--- a/source/src/Makefile
++++ b/source/src/Makefile
+@@ -6,7 +6,6 @@
+ # found to have been caused by the g++ compiler in the past. This seems to have
+ # been fixed now by relaxing the optimization that g++ does, so although we'll
+ # continue using clang++ (just in case), you can use g++ if you prefer.
+-CXX=clang++
+ 
+ # call like 'DEBUGBUILD=1 make' to compile a debug version of AssaultCube.
+ ifdef DEBUGBUILD
+@@ -34,10 +33,8 @@ ifeq ($(ACDEBUG),yes)
+ endif
+ 
+ ifneq (,$(findstring clang,$(CXX)))
+-	CXXFLAGS= -O3 -fomit-frame-pointer
+ 	override CXXFLAGS+= -Wall -fsigned-char
+ else
+-	CXXFLAGS= -O3 -fomit-frame-pointer
+ 	override CXXFLAGS+= -Wall -fsigned-char -ffast-math -rdynamic -Wno-format-zero-length
+ 	ifeq "$(shell expr 'gcc -dumpversion' \>= 8)" "1"
+ 		override CXXFLAGS+= -Wno-stringop-truncation
+@@ -182,7 +179,6 @@ rendermodel.o: rendermodel.cpp
+ 	$(CXX) $(CXXFLAGS) -c -o $@ $(subst -standalone.o,.cpp,$@)
+ 
+ $(CLIENT_OBJS): CXXFLAGS += $(CLIENT_INCLUDES)
+-$(CLIENT_OBJS): $(CLIENT_PCH)
+ $(SERVER_OBJS): CXXFLAGS += $(SERVER_INCLUDES)
+ $(filter-out $(SERVER_OBJS),$(MASTER_OBJS)): CXXFLAGS += $(SERVER_INCLUDES)
+