This patch was taken from NixOS
https://raw.githubusercontent.com/Mindavi/nixpkgs/1a737743a829746e48f4869ac517ff29c23c9d09/pkgs/tools/security/afl/qemu-patches/syscall-glibc2_30.diff
It is based on an unmerged patch against american-fuzzy-lop and was
never merged upstream because the author was unable to sign Google's CLA.
Based on https://github.com/google/AFL/commit/6c917e3d63a2a0685d58c3518524f9615b001893.patch

--- qemu-2.10.0-clean/linux-user/syscall.c	2020-03-12 18:47:47.898592169 +0100
+++ qemu-2.10.0/linux-user/syscall.c	2020-03-13 09:13:42.461809699 +0100
@@ -34,6 +34,7 @@
 #include <sys/resource.h>
 #include <sys/swap.h>
 #include <linux/capability.h>
+#include <linux/sockios.h> // https://lkml.org/lkml/2019/6/3/988
 #include <sched.h>
 #include <sys/timex.h>
 #ifdef __ia64__
@@ -256,7 +257,9 @@ static type name (type1 arg1,type2 arg2,
 #endif
 
 #ifdef __NR_gettid
-_syscall0(int, gettid)
+// taken from https://patchwork.kernel.org/patch/10862231/
+#define __NR_sys_gettid __NR_gettid
+_syscall0(int, sys_gettid)
 #else
 /* This is a replacement for the host gettid() and must return a host
    errno. */
@@ -6219,7 +6222,7 @@ static void *clone_func(void *arg)
     cpu = ENV_GET_CPU(env);
     thread_cpu = cpu;
     ts = (TaskState *)cpu->opaque;
-    info->tid = gettid();
+    info->tid = sys_gettid();
     task_settid(ts);
     if (info->child_tidptr)
         put_user_u32(info->tid, info->child_tidptr);
@@ -6363,9 +6366,9 @@ static int do_fork(CPUArchState *env, un
                mapping.  We can't repeat the spinlock hack used above because
                the child process gets its own copy of the lock.  */
             if (flags & CLONE_CHILD_SETTID)
-                put_user_u32(gettid(), child_tidptr);
+                put_user_u32(sys_gettid(), child_tidptr);
             if (flags & CLONE_PARENT_SETTID)
-                put_user_u32(gettid(), parent_tidptr);
+                put_user_u32(sys_gettid(), parent_tidptr);
             ts = (TaskState *)cpu->opaque;
             if (flags & CLONE_SETTLS)
                 cpu_set_tls (env, newtls);
@@ -11402,7 +11405,7 @@ abi_long do_syscall(void *cpu_env, int n
         break;
 #endif
     case TARGET_NR_gettid:
-        ret = get_errno(gettid());
+        ret = get_errno(sys_gettid());
         break;
 #ifdef TARGET_NR_readahead
     case TARGET_NR_readahead:
c7b0dca328afeabd7b74c9e30df0ba0a6491'>linux-initrd.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/build/linux-initrd.scm?id=8444c7b0dca328afeabd7b74c9e30df0ba0a6491&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-12-15 17:32:10 +0100'>2020-12-15</span></td><td><a href='/guix/commit/gnu/build/linux-initrd.scm?id=6a060ff27ff68384d7c90076baa36c349fff689d'>store-copy: 'populate-store' can optionally deduplicate files.</a><span class='msg-avail'>...<span class='msg-tooltip'>Until now deduplication was performed as an additional pass after
copying files, which involve re-traversing all the files that had just
been copied.

* guix/store/deduplication.scm (copy-file/deduplicate): New procedure.
* tests/store-deduplication.scm ("copy-file/deduplicate"): New test.
* guix/build/store-copy.scm (populate-store): Add #:deduplicate?
parameter and honor it.
* tests/gexp.scm ("gexp-&gt;derivation, store copy"): Pass #:deduplicate? #f
to 'populate-store'.
* gnu/build/image.scm (initialize-root-partition): Pass #:deduplicate?
to 'populate-store'.  Pass #:deduplicate? #f to 'register-closure'.
* gnu/build/vm.scm (root-partition-initializer): Likewise.
* gnu/build/install.scm (populate-single-profile-directory): Pass
 #:deduplicate? #f to 'populate-store'.
* gnu/build/linux-initrd.scm (build-initrd): Likewise.
* guix/scripts/pack.scm (self-contained-tarball)[import-module?]: New
procedure.
[build]: Pass it as an argument to 'source-module-closure'.
* guix/scripts/pack.scm (squashfs-image)[build]: Wrap in
'with-extensions'.
* gnu/system/linux-initrd.scm (expression-&gt;initrd)[import-module?]: New
procedure.
[builder]: Pass it to 'source-module-closure'.
* gnu/system/install.scm (cow-store-service-type)[import-module?]: New
procedure.  Pass it to 'source-module-closure'.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-11-21 12:39:14 +0100'>2020-11-21</span></td><td><a href='/guix/commit/gnu/build/linux-initrd.scm?id=2200bb214690ebc78b9fa42887ac9dfb8035bd4f'>linux-initrd: Remove unnecessary timestamp reset phase.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/build/linux-initrd.scm (write-cpio-archive): Mention timestamps in
docstring.
(build-initrd): Remove unnecessary timestamp reset phase.
</span></span></td><td>Ludovic Courtès</td></tr>