From d856402e7176e5a03c5c578f0efc1be968be3257 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20P=C3=A9ron?= <peron.clem@gmail.com>
Date: Sat, 22 Aug 2026 05:05:20 +0200
Subject: [PATCH 1/2] gh-156115: Use the simulator deployment-target flag for
 iOS simulator builds (#156116)

Ensures that CFLAGS and LDFLAGS use -mios-simulator-version-min, rather
than the device-based -mios-version-min. This only matters if the CFLAGS
and LDFLAGS are used in a bare call to clang without a -target; but that is
a legal usage, so it's worth catching.
---
 .../Build/2026-08-20-14-02-33.gh-issue-156115.KXr8wU.rst | 4 ++++
 configure                                                | 9 +++++++--
 configure.ac                                             | 8 ++++++--
 3 files changed, 17 insertions(+), 4 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Build/2026-08-20-14-02-33.gh-issue-156115.KXr8wU.rst

diff --git a/Misc/NEWS.d/next/Build/2026-08-20-14-02-33.gh-issue-156115.KXr8wU.rst b/Misc/NEWS.d/next/Build/2026-08-20-14-02-33.gh-issue-156115.KXr8wU.rst
new file mode 100644
index 000000000000000..612180d3b65db21
--- /dev/null
+++ b/Misc/NEWS.d/next/Build/2026-08-20-14-02-33.gh-issue-156115.KXr8wU.rst
@@ -0,0 +1,4 @@
+iOS simulator builds are now configured with
+``-mios-simulator-version-min`` instead of the device's
+``-mios-version-min``. The device flag made the linker reject libraries
+resolved from the simulator SDK, so library detection silently failed.
diff --git a/configure b/configure
index ea560d600722592..1b03d29e91a8336 100755
--- a/configure
+++ b/configure
@@ -4895,8 +4895,13 @@ case $host in #(
      ;;
 esac
 
-case $ac_sys_system in #(
-  iOS) :
+case $host in #(
+  *-apple-ios*-simulator) :
+
+    as_fn_append CFLAGS " -mios-simulator-version-min=${IPHONEOS_DEPLOYMENT_TARGET}"
+    as_fn_append LDFLAGS " -mios-simulator-version-min=${IPHONEOS_DEPLOYMENT_TARGET}"
+   ;; #(
+  *-apple-ios*) :
 
     as_fn_append CFLAGS " -mios-version-min=${IPHONEOS_DEPLOYMENT_TARGET}"
     as_fn_append LDFLAGS " -mios-version-min=${IPHONEOS_DEPLOYMENT_TARGET}"
diff --git a/configure.ac b/configure.ac
index 7dfc6ca29297a8b..99444990cf0c741 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1006,8 +1006,12 @@ AS_CASE([$host],
 )
 
 dnl Add the compiler flag for the iOS minimum supported OS version.
-AS_CASE([$ac_sys_system],
-  [iOS], [
+AS_CASE([$host],
+  [*-apple-ios*-simulator], [
+    AS_VAR_APPEND([CFLAGS], [" -mios-simulator-version-min=${IPHONEOS_DEPLOYMENT_TARGET}"])
+    AS_VAR_APPEND([LDFLAGS], [" -mios-simulator-version-min=${IPHONEOS_DEPLOYMENT_TARGET}"])
+  ],
+  [*-apple-ios*], [
     AS_VAR_APPEND([CFLAGS], [" -mios-version-min=${IPHONEOS_DEPLOYMENT_TARGET}"])
     AS_VAR_APPEND([LDFLAGS], [" -mios-version-min=${IPHONEOS_DEPLOYMENT_TARGET}"])
   ],

From 918fb3aec907baf8d9b6181570ff308529be16a3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20P=C3=A9ron?= <peron.clem@gmail.com>
Date: Sat, 22 Aug 2026 05:51:49 +0200
Subject: [PATCH 2/2] gh-156112: Load the ObjC runtime by name when
 find_library() cannot resolve it (#156113)

Provides a fallback name for the ObjC runtime library on iOS, and improved error
handling when that library cannot be loaded.
---
 Lib/_ios_support.py                                 | 13 ++++++++-----
 .../2026-08-20-13-50-49.gh-issue-156112.yEcma8.rst  |  4 ++++
 2 files changed, 12 insertions(+), 5 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Library/2026-08-20-13-50-49.gh-issue-156112.yEcma8.rst

diff --git a/Lib/_ios_support.py b/Lib/_ios_support.py
index 20467a7c2bcaeb0..cc51aa504916e36 100644
--- a/Lib/_ios_support.py
+++ b/Lib/_ios_support.py
@@ -10,12 +10,15 @@
 else:
     # ctypes is available. Load the ObjC library, and wrap the objc_getClass,
     # sel_registerName methods
-    lib = util.find_library("objc")
-    if lib is None:
-        # Failed to load the objc library
-        raise ImportError("ObjC runtime library couldn't be loaded")
+    # find_library() resolves a system library through the dyld shared cache,
+    # which needs _dyld_shared_cache_contains_path(); that is unavailable before
+    # iOS 14, so fall back to the bare name, which dyld resolves by itself.
+    lib = util.find_library("objc") or "libobjc.dylib"
 
-    objc = cdll.LoadLibrary(lib)
+    try:
+        objc = cdll.LoadLibrary(lib)
+    except OSError:
+        raise ImportError("ObjC runtime library couldn't be loaded")
     objc.objc_getClass.restype = c_void_p
     objc.objc_getClass.argtypes = [c_char_p]
     objc.sel_registerName.restype = c_void_p
diff --git a/Misc/NEWS.d/next/Library/2026-08-20-13-50-49.gh-issue-156112.yEcma8.rst b/Misc/NEWS.d/next/Library/2026-08-20-13-50-49.gh-issue-156112.yEcma8.rst
new file mode 100644
index 000000000000000..ba92df3c5cb6c1d
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-08-20-13-50-49.gh-issue-156112.yEcma8.rst
@@ -0,0 +1,4 @@
+:mod:`!_ios_support` no longer fails to import when
+:func:`ctypes.util.find_library` cannot resolve the ObjC runtime through the
+dyld shared cache, as is the case on iOS 13. The runtime is now loaded by name,
+which dyld resolves against the cache directly.