As can be seen on

http://build-failures.rhaalovely.net/sparc64/2024-05-18/summary.log

spirv-tools is the immediate blocker for many missing ports on sparc64.
It needs to link against stdc++fs with ports-gcc:

http://build-failures.rhaalovely.net/sparc64/2024-05-18/graphics/spirv-tools.log

The diff below uses the same approach as the one used by jca for glslang

https://github.com/openbsd/ports/commit/eb51153047ff2fdba5334b386c814557b77857ba

Packages on sparc64 and arm64.

Index: Makefile
===================================================================
RCS file: /cvs/ports/graphics/spirv-tools/Makefile,v
diff -u -p -r1.20 Makefile
--- Makefile	20 May 2024 15:46:33 -0000	1.20
+++ Makefile	21 May 2024 07:57:39 -0000
@@ -31,7 +31,16 @@ BUILD_DEPENDS =	graphics/spirv-headers
 
 CONFIGURE_ARGS =	-DSPIRV-Headers_SOURCE_DIR="${LOCALBASE}"
 
+SUBST_VARS =	ADDITIONAL_LIBRARIES
+
+pre-configure:
+	${SUBST_CMD} ${WRKSRC}/tools/CMakeLists.txt
+
 # effcee is missing to build tests
 NO_TEST =	Yes
 
 .include <bsd.port.mk>
+
+.if ${CHOSEN_COMPILER} == ports-gcc
+ADDITIONAL_LIBRARIES = stdc++fs
+.endif
Index: patches/patch-tools_CMakeLists_txt
===================================================================
RCS file: patches/patch-tools_CMakeLists_txt
diff -N patches/patch-tools_CMakeLists_txt
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ patches/patch-tools_CMakeLists_txt	21 May 2024 07:58:40 -0000
@@ -0,0 +1,14 @@
+Add -lstdc++fs for ports-gcc
+
+Index: tools/CMakeLists.txt
+--- tools/CMakeLists.txt.orig
++++ tools/CMakeLists.txt
+@@ -74,7 +74,7 @@ if (NOT ${SPIRV_SKIP_EXECUTABLES})
+                            objdump/extract_source.cpp
+                            util/cli_consumer.cpp
+                            ${COMMON_TOOLS_SRCS}
+-                      LIBS ${SPIRV_TOOLS_FULL_VISIBILITY})
++                      LIBS ${SPIRV_TOOLS_FULL_VISIBILITY} ${ADDITIONAL_LIBRARIES})
+     target_include_directories(spirv-objdump PRIVATE ${spirv-tools_SOURCE_DIR}
+                                                      ${SPIRV_HEADER_INCLUDE_DIR})
+     set(SPIRV_INSTALL_TARGETS ${SPIRV_INSTALL_TARGETS} spirv-objdump)