diff -ruN llvm-22.1.8/llvm/include/llvm/ADT/bit.h llvm-22.1.8-banan_os/llvm/include/llvm/ADT/bit.h
--- llvm-22.1.8/llvm/include/llvm/ADT/bit.h	2026-06-16 01:33:53.000000000 +0300
+++ llvm-22.1.8-banan_os/llvm/include/llvm/ADT/bit.h	2026-07-07 10:03:36.848199127 +0300
@@ -30,7 +30,8 @@
 
 #if defined(__linux__) || defined(__GNU__) || defined(__HAIKU__) ||            \
     defined(__Fuchsia__) || defined(__EMSCRIPTEN__) || defined(__NetBSD__) ||  \
-    defined(__OpenBSD__) || defined(__DragonFly__) || defined(__managarm__)
+    defined(__OpenBSD__) || defined(__DragonFly__) || defined(__managarm__) || \
+    defined(__banan_os__)
 #include <endian.h>
 #elif defined(_AIX)
 #include <sys/machine.h>
diff -ruN llvm-22.1.8/llvm/include/llvm/Support/ExitCodes.h llvm-22.1.8-banan_os/llvm/include/llvm/Support/ExitCodes.h
--- llvm-22.1.8/llvm/include/llvm/Support/ExitCodes.h	2026-06-16 01:33:53.000000000 +0300
+++ llvm-22.1.8-banan_os/llvm/include/llvm/Support/ExitCodes.h	2026-07-07 10:03:36.965344890 +0300
@@ -20,7 +20,7 @@
 
 #if HAVE_SYSEXITS_H
 #include <sysexits.h>
-#elif __MVS__ || defined(_WIN32)
+#elif __MVS__ || defined(_WIN32) || defined(__banan_os__)
 // <sysexits.h> does not exist on z/OS and Windows. The only value used in LLVM
 // is EX_IOERR, which is used to signal a special error condition (broken pipe).
 // Define the macro with its usual value from BSD systems, which is chosen to
diff -ruN llvm-22.1.8/llvm/lib/Support/Unix/Path.inc llvm-22.1.8-banan_os/llvm/lib/Support/Unix/Path.inc
--- llvm-22.1.8/llvm/lib/Support/Unix/Path.inc	2026-06-16 01:33:53.000000000 +0300
+++ llvm-22.1.8-banan_os/llvm/lib/Support/Unix/Path.inc	2026-07-07 10:03:36.987545022 +0300
@@ -111,7 +111,7 @@
 #endif
 
 #if defined(__NetBSD__) || defined(__DragonFly__) || defined(__GNU__) ||       \
-    defined(__MVS__)
+    defined(__MVS__) || defined(__banan_os__)
 #define STATVFS_F_FLAG(vfs) (vfs).f_flag
 #else
 #define STATVFS_F_FLAG(vfs) (vfs).f_flags
@@ -254,7 +254,7 @@
   if (getprogpath(exe_path, argv0) != NULL)
     return exe_path;
 #elif defined(__linux__) || defined(__CYGWIN__) || defined(__gnu_hurd__) ||    \
-    defined(__managarm__)
+    defined(__managarm__) || defined(__banan_os__)
   char exe_path[PATH_MAX];
   const char *aPath = "/proc/self/exe";
   if (sys::fs::exists(aPath)) {
@@ -284,9 +284,11 @@
       return std::string(real_path);
 #endif
   }
+#if !defined(__banan_os__)
   // Fall back to the classical detection.
   if (getprogpath(exe_path, argv0))
     return exe_path;
+#endif
 #elif defined(__OpenBSD__) || defined(__HAIKU__)
   char exe_path[PATH_MAX];
   // argv[0] only
@@ -520,6 +522,9 @@
 #elif defined(__HAIKU__)
   // Haiku doesn't expose this information.
   return false;
+#elif defined(__banan_os__)
+  // banan-os doesn't expose this information.
+  return false;
 #elif defined(__sun)
   // statvfs::f_basetype contains a null-terminated FSType name of the mounted
   // target
diff -ruN llvm-22.1.8/llvm/lib/Support/Unix/Process.inc llvm-22.1.8-banan_os/llvm/lib/Support/Unix/Process.inc
--- llvm-22.1.8/llvm/lib/Support/Unix/Process.inc	2026-06-16 01:33:53.000000000 +0300
+++ llvm-22.1.8-banan_os/llvm/lib/Support/Unix/Process.inc	2026-07-07 10:03:37.017664239 +0300
@@ -37,6 +37,9 @@
 #ifdef HAVE_SYS_IOCTL_H
 #include <sys/ioctl.h>
 #endif
+#ifdef __banan_os__
+#include <termios.h>
+#endif
 
 //===----------------------------------------------------------------------===//
 //=== WARNING: Implementation here must contain only generic UNIX code that
diff -ruN llvm-22.1.8/llvm/lib/Support/Unix/Program.inc llvm-22.1.8-banan_os/llvm/lib/Support/Unix/Program.inc
--- llvm-22.1.8/llvm/lib/Support/Unix/Program.inc	2026-06-16 01:33:53.000000000 +0300
+++ llvm-22.1.8-banan_os/llvm/lib/Support/Unix/Program.inc	2026-07-07 10:03:37.031901635 +0300
@@ -334,7 +334,7 @@
 namespace llvm {
 namespace sys {
 
-#if defined(_AIX)
+#if defined(_AIX) || defined(__banan_os__)
 static pid_t(wait4)(pid_t pid, int *status, int options, struct rusage *usage);
 #elif !defined(__Fuchsia__)
 using ::wait4;
@@ -375,6 +375,12 @@
   // would cause the call here to fail with ECHILD).
   return ::wait4(pid, status, options & ~WNOHANG, usage);
 }
+#elif defined(__banan_os__)
+pid_t(llvm::sys::wait4)(pid_t pid, int *status, int options,
+                        struct rusage *usage) {
+    memset(usage, 0, sizeof(struct rusage));
+    return ::waitpid(pid, status, options);
+}
 #endif
 
 ProcessInfo llvm::sys::Wait(const ProcessInfo &PI,
diff -ruN llvm-22.1.8/llvm/lib/Support/Unix/Threading.inc llvm-22.1.8-banan_os/llvm/lib/Support/Unix/Threading.inc
--- llvm-22.1.8/llvm/lib/Support/Unix/Threading.inc	2026-06-16 01:33:53.000000000 +0300
+++ llvm-22.1.8-banan_os/llvm/lib/Support/Unix/Threading.inc	2026-07-07 10:03:37.256828558 +0300
@@ -70,6 +70,10 @@
 #include <OS.h> // For B_OS_NAME_LENGTH
 #endif
 
+#if defined(__banan_os__)
+#include <unistd.h> // For sysconf()
+#endif
+
 namespace llvm {
 pthread_t
 llvm_execute_on_thread_impl(void *(*ThreadFunc)(void *), void *Arg,
@@ -121,7 +125,7 @@
 
 pthread_t llvm_thread_get_id_impl(pthread_t Thread) { return Thread; }
 
-pthread_t llvm_thread_get_current_id_impl() { return ::pthread_self(); }
+pthread_t llvm_thread_get_current_id_impl() { return pthread_self(); }
 
 } // namespace llvm
 
@@ -148,6 +152,8 @@
   return uint64_t(syscall(__NR_gettid));
 #elif defined(_AIX)
   return uint64_t(thread_self());
+#elif defined(__banan_os__)
+  return uint64_t(pthread_self()->id);
 #else
   return uint64_t(pthread_self());
 #endif
@@ -171,6 +177,8 @@
   return 24;
 #elif defined(__CYGWIN__)
   return 16;
+#elif defined(__banan_os__)
+  return sizeof(uthread::name);
 #else
   return 0;
 #endif
@@ -393,7 +401,7 @@
   }
   return CPU_COUNT(&Enabled);
 }
-#elif (defined(__linux__) && defined(__s390x__)) || defined(_AIX)
+#elif (defined(__linux__) && defined(__s390x__)) || defined(_AIX) || defined(__banan_os__)
 static int computeHostNumPhysicalCores() {
   return sysconf(_SC_NPROCESSORS_ONLN);
 }