kexec-tools: fix compiling with llvm

Fixes #317526

pkgs/os-specific/linux/kexec-tools/default.nix

@@ -23,7 +23,7 @@ stdenv.mkDerivation rec {
       url = "https://github.com/horms/kexec-tools/commit/328de8e00e298f00d7ba6b25dc3950147e9642e6.patch";
       hash = "sha256-wVQI4oV+hBLq3kGIp2+F5J3f6s/TypDu3Xq583KYc3U=";
     })
-  ];
+  ] ++ lib.optional (stdenv.hostPlatform.useLLVM or false) ./fix-purgatory-llvm-libunwind.patch;
 
   hardeningDisable = [ "format" "pic" "relro" "pie" ];
 

pkgs/os-specific/linux/kexec-tools/fix-purgatory-llvm-libunwind.patch

@@ -0,0 +1,11 @@
+--- a/purgatory/Makefile	2024-06-06 23:59:33.089005832 -0700
++++ b/purgatory/Makefile	2024-06-06 23:59:56.761169892 -0700
+@@ -62,7 +62,7 @@
+ $(PURGATORY): LDFLAGS=$($(ARCH)_PURGATORY_EXTRA_CFLAGS)\
+ 			-Wl,--no-undefined -nostartfiles -nostdlib \
+ 			-nodefaultlibs -e purgatory_start -r \
+-			-Wl,-Map=$(PURGATORY_MAP)
++			-Wl,-Map=$(PURGATORY_MAP) -static
+ 
+ $(PURGATORY): $(PURGATORY_OBJS)
+ 	$(MKDIR) -p $(@D)

pkgs/top-level/all-packages.nix

@@ -9474,17 +9474,7 @@ with pkgs;
 
   kestrel = callPackage ../tools/security/kestrel { };
 
-  kexec-tools = callPackage ../os-specific/linux/kexec-tools {
-    # clangStdenv fails with
-    # purgatory/arch/i386/entry32-16.S:23:2: error: unknown directive
-    #  .arch i386
-    #  ^
-    # purgatory/arch/i386/entry32-16.S:115:11: error: unknown token in expression
-    #  ljmp %cs:*(realdest - entry16)
-    #           ^
-    # make: *** [Makefile:128: purgatory/arch/i386/entry32-16.o] Error 1
-    stdenv = gccStdenv;
-  };
+  kexec-tools = callPackage ../os-specific/linux/kexec-tools { };
 
   keepkey-agent = with python3Packages; toPythonApplication keepkey-agent;