Add support for building with HWASAN

Co-authored-by: Florian Mayer <fmayer@google.com>
Co-authored-by: Anna <araslanova.anna.a@gmail.com>

Author: 3 people

Doc/using/configure.rst

@@ -1015,6 +1015,16 @@ Debug options
 
    .. versionadded:: 3.6
 
+.. option:: --with-hwaddress-sanitizer
+
+   Enable HWAddressSanitizer memory error detector, ``hwasan`` (default is no).
+   Note that on x86-64 this uses `page aliasing
+   <https://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html#supported-architectures>`_,
+   which only tags heap allocations and is unsafe for programs that ``fork()``,
+   including much of the test suite.
+
+   .. versionadded:: 3.16
+
 .. option:: --with-memory-sanitizer
 
    Enable MemorySanitizer allocation error detector, ``msan`` (default is no).

Doc/whatsnew/3.16.rst

@@ -934,6 +934,11 @@ Build changes
 
   (Contributed by Stan Ulbrych in :gh:`139314`.)
 
+* Add the :option:`--with-hwaddress-sanitizer` :program:`configure` option to
+  build with `HWAddressSanitizer <https://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html>`_.
+
+  (Contributed by Stan Ulbrych, Florian Mayer and AnnaAr321 in :gh:`156049`.)
+
 
 C API changes
 =============

Include/pyport.h

@@ -562,6 +562,12 @@ extern "C" {
 #      define _Py_NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address))
 #    endif
 #  endif
+#  if __has_feature(hwaddress_sanitizer)
+#    if !defined(_Py_ADDRESS_SANITIZER)
+#      define _Py_ADDRESS_SANITIZER
+#      define _Py_NO_SANITIZE_ADDRESS __attribute__((no_sanitize("hwaddress")))
+#    endif
+#  endif
 #  if __has_feature(thread_sanitizer)
 #    if !defined(_Py_THREAD_SANITIZER)
 #      define _Py_THREAD_SANITIZER
@@ -572,6 +578,9 @@ extern "C" {
 #  if defined(__SANITIZE_ADDRESS__)
 #    define _Py_ADDRESS_SANITIZER
 #    define _Py_NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address))
+#  elif defined(__SANITIZE_HWADDRESS__)
+#    define _Py_ADDRESS_SANITIZER
+#    define _Py_NO_SANITIZE_ADDRESS __attribute__((no_sanitize("hwaddress")))
 #  endif
 #  if defined(__SANITIZE_THREAD__)
 #    define _Py_THREAD_SANITIZER

Lib/test/support/__init__.py

@@ -463,7 +463,9 @@ def check_sanitizer(*, address=False, memory=False, ub=False, thread=False,
     )
     address_sanitizer = (
         '-fsanitize=address' in cflags or
-        '--with-address-sanitizer' in config_args
+        '-fsanitize=hwaddress' in cflags or
+        '--with-address-sanitizer' in config_args or
+        '--with-hwaddress-sanitizer' in config_args
     )
     ub_sanitizer = (
         '-fsanitize=undefined' in cflags or

Misc/NEWS.d/next/Build/2026-08-31-15-50-04.gh-issue-156049.FCf6hP.rst

@@ -0,0 +1,2 @@
+Add :option:`--with-hwaddress-sanitizer` to build with `HWAddressSanitizer
+<https://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html>`_.

configure

@@ -3533,6 +3533,30 @@ with_pymalloc="no"
 ],
 [AC_MSG_RESULT([no])])
 
+AC_MSG_CHECKING([for --with-hwaddress-sanitizer])
+AC_ARG_WITH(
+  [hwaddress_sanitizer],
+  [AS_HELP_STRING(
+    [--with-hwaddress-sanitizer],
+    [enable HWAddressSanitizer memory error detector, 'hwasan' (default is no)]
+  )],
+[
+AC_MSG_RESULT([$withval])
+hwasan_flags="-fsanitize=hwaddress"
+# x86-64 lacks address tagging, so HWASan needs the page aliasing mode there.
+# See https://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html#supported-architectures
+AS_CASE([$host_cpu],
+  [x86_64|amd64], [hwasan_flags="$hwasan_flags -fsanitize-hwaddress-experimental-aliasing"]
+)
+AX_CHECK_COMPILE_FLAG([$hwasan_flags],[
+BASECFLAGS="$hwasan_flags -fno-omit-frame-pointer $BASECFLAGS"
+LDFLAGS="$hwasan_flags $LDFLAGS"
+],[AC_MSG_ERROR([The selected compiler doesn't support hardware address sanitizer])])
+# HWASan works by controlling memory allocation, our own malloc interferes.
+with_pymalloc="no"
+],
+[AC_MSG_RESULT([no])])
+
 AC_MSG_CHECKING([for --with-memory-sanitizer])
 AC_ARG_WITH(
   [memory_sanitizer],