thinlto-cachedir.patch

diff -Naur a/Makefile b/Makefile
--- a/Makefile	2024-03-26 23:22:50.000000000 +0100
+++ b/Makefile	2024-04-03 17:25:28.110772701 +0200
@@ -939,7 +939,7 @@
 ifdef CONFIG_LTO_CLANG
 ifdef CONFIG_LTO_CLANG_THIN
 CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
-KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
+KBUILD_LDFLAGS	+= --thinlto-cache-dir=/tmp/$(extmod_prefix).thinlto-cache
 else
 CC_FLAGS_LTO	:= -flto
 endif
@@ -1471,7 +1471,7 @@
 # Directories & files removed with 'make clean'
 CLEAN_FILES += vmlinux.symvers modules-only.symvers \
 	       modules.builtin modules.builtin.modinfo modules.nsdeps \
-	       compile_commands.json .thinlto-cache rust/test \
+	       compile_commands.json /tmp/.thinlto-cache rust/test \
 	       rust-project.json .vmlinux.objs .vmlinux.export.c
 
 # Directories & files removed with 'make mrproper'
@@ -1775,7 +1775,7 @@
 
 clean-dirs := $(KBUILD_EXTMOD)
 clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
-	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
+	$(KBUILD_EXTMOD)/compile_commands.json /tmp/$(KBUILD_EXTMOD)/.thinlto-cache
 
 PHONY += prepare
 # now expand this into a simple variable to reduce the cost of shell evaluations