bpftrace: fix build with libbpf 0.6.0

libbpf 0.6.0 relies on typeof in bpf/btf.h to pick the right version of
btf_dump__new() but that's not valid c++.
see https://github.com/iovisor/bpftrace/issues/2068

pkgs/os-specific/linux/bpftrace/btf-dump-new-0.6.0.patch

@@ -0,0 +1,39 @@
+diff -ur source/src/btf.cpp new/src/btf.cpp
+--- source/src/btf.cpp	1970-01-01 09:00:01.000000000 +0900
++++ new/src/btf.cpp	2021-12-04 21:46:59.337023489 +0900
+@@ -225,7 +225,7 @@
+   char err_buf[256];
+   int err;
+ 
+-  dump = btf_dump__new(btf, nullptr, &opts, dump_printf);
++  dump = btf_dump__new_deprecated(btf, nullptr, &opts, dump_printf);
+   err = libbpf_get_error(dump);
+   if (err)
+   {
+@@ -496,7 +496,7 @@
+   char err_buf[256];
+   int err;
+ 
+-  dump = btf_dump__new(btf, nullptr, &opts, dump_printf);
++  dump = btf_dump__new_deprecated(btf, nullptr, &opts, dump_printf);
+   err = libbpf_get_error(dump);
+   if (err)
+   {
+@@ -554,7 +554,7 @@
+   char err_buf[256];
+   int err;
+ 
+-  dump = btf_dump__new(btf, nullptr, &opts, dump_printf);
++  dump = btf_dump__new_deprecated(btf, nullptr, &opts, dump_printf);
+   err = libbpf_get_error(dump);
+   if (err)
+   {
+@@ -648,7 +648,7 @@
+   char err_buf[256];
+   int err;
+ 
+-  dump = btf_dump__new(btf, nullptr, &opts, dump_printf);
++  dump = btf_dump__new_deprecated(btf, nullptr, &opts, dump_printf);
+   err = libbpf_get_error(dump);
+   if (err)
+   {

pkgs/os-specific/linux/bpftrace/default.nix

@@ -17,6 +17,11 @@ stdenv.mkDerivation rec {
     sha256 = "sha256-rlaajNfpoiMtU/4aNAnbQ0VixPz9/302TZMarGzsb58=";
   };
 
+  # libbpf 0.6.0 relies on typeof in bpf/btf.h to pick the right version of
+  # btf_dump__new() but that's not valid c++.
+  # see https://github.com/iovisor/bpftrace/issues/2068
+  patches = [ ./btf-dump-new-0.6.0.patch ];
+
   buildInputs = with llvmPackages;
     [ llvm libclang
       elfutils libelf bcc