[libcxx-commits] [libcxx] [libc++] Port to Haiku (PR #196271)

[Elaine Gibson via libcxx-commits]

https://github.com/ypsvlq updated https://github.com/llvm/llvm-project/pull/196271

>From 81318913e142d3f068e5cfc48bf894736d0123fe Mon Sep 17 00:00:00 2001
From: Elaine Gibson <ypsvlq at gmail.com>
Date: Thu, 13 Aug 2026 23:50:43 +0100
Subject: [PATCH] [libc++] Port to Haiku
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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Co-authored-by: Jérôme Duval <jerome.duval at gmail.com>
---
 libcxx/cmake/config-ix.cmake                  |  4 ++++
 libcxx/include/CMakeLists.txt                 |  1 +
 libcxx/include/__config                       |  3 ++-
 libcxx/include/__locale_dir/ctype_base.h      | 13 +++++++++++++
 libcxx/include/__locale_dir/locale_base_api.h |  2 ++
 libcxx/include/module.modulemap.in            |  1 +
 libcxx/src/include/config_elast.h             |  2 ++
 7 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/libcxx/cmake/config-ix.cmake b/libcxx/cmake/config-ix.cmake
index 270d80575adcf..e6f114979e9de 100644
--- a/libcxx/cmake/config-ix.cmake
+++ b/libcxx/cmake/config-ix.cmake
@@ -122,6 +122,10 @@ elseif(ANDROID)
   set(LIBCXX_HAS_PTHREAD_LIB NO)
   set(LIBCXX_HAS_RT_LIB NO)
   set(LIBCXX_HAS_ATOMIC_LIB NO)
+elseif(HAIKU)
+  set(LIBCXX_HAS_PTHREAD_LIB NO)
+  set(LIBCXX_HAS_RT_LIB NO)
+  set(LIBCXX_HAS_ATOMIC_LIB NO)
 elseif(PICOLIBC)
   set(LIBCXX_HAS_PTHREAD_LIB NO)
   set(LIBCXX_HAS_RT_LIB NO)
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index a1d6a09aa6b20..f615ce92b0727 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -556,6 +556,7 @@ set(files
   __locale_dir/support/bsd_like.h
   __locale_dir/support/freebsd.h
   __locale_dir/support/fuchsia.h
+  __locale_dir/support/haiku.h
   __locale_dir/support/linux.h
   __locale_dir/support/llvm_libc.h
   __locale_dir/support/netbsd.h
diff --git a/libcxx/include/__config b/libcxx/include/__config
index 8c2b0abfb450f..4fb9be889dd24 100644
--- a/libcxx/include/__config
+++ b/libcxx/include/__config
@@ -214,7 +214,8 @@ typedef __char32_t char32_t;
         defined(__APPLE__) ||                                                                                          \
         defined(__MVS__) ||                                                                                            \
         defined(_AIX) ||                                                                                               \
-        defined(__EMSCRIPTEN__)
+        defined(__EMSCRIPTEN__) ||                                                                                     \
+        defined(__HAIKU__)
 // clang-format on
 #      undef _LIBCPP_HAS_THREAD_API_PTHREAD
 #      define _LIBCPP_HAS_THREAD_API_PTHREAD 1
diff --git a/libcxx/include/__locale_dir/ctype_base.h b/libcxx/include/__locale_dir/ctype_base.h
index 1188928d78611..ae2f476611089 100644
--- a/libcxx/include/__locale_dir/ctype_base.h
+++ b/libcxx/include/__locale_dir/ctype_base.h
@@ -168,6 +168,19 @@ class _LIBCPP_EXPORTED_FROM_ABI ctype_base {
   static const mask blank  = __ISBLANK;
 #    endif
   static const mask __regex_word = 0x8000;
+#  elif defined(__HAIKU__)
+  typedef unsigned short mask;
+  static const mask space        = _ISspace;
+  static const mask print        = _ISprint;
+  static const mask cntrl        = _IScntrl;
+  static const mask upper        = _ISupper;
+  static const mask lower        = _ISlower;
+  static const mask alpha        = _ISalpha;
+  static const mask digit        = _ISdigit;
+  static const mask punct        = _ISpunct;
+  static const mask xdigit       = _ISxdigit;
+  static const mask blank        = _ISblank;
+  static const mask __regex_word = 0x80;
 #  else
 #    error unknown rune table for this platform -- do you mean to define _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE?
 #  endif
diff --git a/libcxx/include/__locale_dir/locale_base_api.h b/libcxx/include/__locale_dir/locale_base_api.h
index 017d971ec72ba..c35c0bd33f3c1 100644
--- a/libcxx/include/__locale_dir/locale_base_api.h
+++ b/libcxx/include/__locale_dir/locale_base_api.h
@@ -128,6 +128,8 @@
 #    include <__locale_dir/support/newlib.h>
 #  elif defined(_AIX)
 #    include <__locale_dir/support/aix.h>
+#  elif defined(__HAIKU__)
+#    include <__locale_dir/support/haiku.h>
 #  else
 
 // TODO: This is a temporary definition to bridge between the old way we defined the locale base API
diff --git a/libcxx/include/module.modulemap.in b/libcxx/include/module.modulemap.in
index 4512cc71153ca..da82525b48899 100644
--- a/libcxx/include/module.modulemap.in
+++ b/libcxx/include/module.modulemap.in
@@ -1620,6 +1620,7 @@ module std {
       textual header "__locale_dir/support/bsd_like.h"
       textual header "__locale_dir/support/freebsd.h"
       textual header "__locale_dir/support/fuchsia.h"
+      textual header "__locale_dir/support/haiku.h"
       textual header "__locale_dir/support/linux.h"
       textual header "__locale_dir/support/llvm_libc.h"
       textual header "__locale_dir/support/netbsd.h"
diff --git a/libcxx/src/include/config_elast.h b/libcxx/src/include/config_elast.h
index 8aa9355c4e7f3..cb571f1a8bcf6 100644
--- a/libcxx/src/include/config_elast.h
+++ b/libcxx/src/include/config_elast.h
@@ -33,6 +33,8 @@
 // No _LIBCPP_ELAST needed on WASI
 #elif defined(__EMSCRIPTEN__)
 // No _LIBCPP_ELAST needed on Emscripten
+#elif defined(__HAIKU__)
+// No _LIBCPP_ELAST needed on Haiku
 #elif defined(__linux__) || _LIBCPP_HAS_MUSL_LIBC
 #  define _LIBCPP_ELAST 4095
 #elif defined(__APPLE__)