Issue #569: Use old linker when building with Xcode 15

A known issue with Xcode 15 is that weak symbols don't work
when targetting earlier macOS versions (before macOS 12). Switch
to using the old linker until that issue is fixed.

docs/changelog.rst

@@ -163,6 +163,9 @@ Version 10.0
 * ``dispatch.dispatch_source_t`` is renamed to ``dispatch.dispatch_source_type_t``
   to match the type name in C code.
 
+* :issue:`569`: Xcode 15 has a bug when using weak symbols and targeting older macOS
+  versions. Switch to the old linker when detecting Xcode 15.
+
 Version 9.2.1
 -------------
 

pyobjc-core/Tools/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-core/setup.py

@@ -92,8 +92,8 @@ def get_sdk_level(sdk):
     # "-O0",
     "-g",
     # "-O0",
-    # "-O3",
-    # "-flto=thin",
+    "-O3",
+    "-flto=thin",
     # XXX: Use object_path_lto (during linking?)
     "-UNDEBUG",
 ]
@@ -576,6 +576,16 @@ def finalize_options(self):
                 CFLAGS.append("-DNO_OBJC2_RUNTIME")
                 EXT_CFLAGS.append("-DNO_OBJC2_RUNTIME")
 
+        lines = subprocess.check_output(
+            ["xcodebuild", "-version"], text=True
+        ).splitlines()
+        if lines[0].startswith("Xcode"):
+            xcode_vers = int(lines[0].split()[-1].split(".")[0])
+            if xcode_vers >= 15:
+                for var in (OBJC_LDFLAGS,):
+                    print("Use old linker with Xcode 15 or later")
+                    var.append("-Wl,-ld_classic")
+
     def run(self):
         verify_platform()
 

pyobjc-framework-AVFoundation/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AVKit/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AVRouting/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-Accessibility/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-Accounts/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AdServices/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AdSupport/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AddressBook/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AppTrackingTransparency/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AppleScriptKit/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AppleScriptObjC/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-ApplicationServices/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AudioVideoBridging/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AuthenticationServices/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-AutomaticAssessmentConfiguration/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-Automator/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-BackgroundAssets/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-BusinessChat/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-CFNetwork/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-CalendarStore/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")
 

pyobjc-framework-CallKit/pyobjc_setup.py

@@ -510,6 +510,15 @@ def Extension(*args, **kwds):
             % (tuple(map(int, os_level.split(".")[:2])))
         )
 
+    # XCode 15 has a bug w.r.t. weak linking for older macOS versions,
+    # fall back to older linker when using that compiler.
+    # XXX: This should be in _fixup_compiler but doesn't work there...
+    lines = subprocess.check_output(["xcodebuild", "-version"], text=True).splitlines()
+    if lines[0].startswith("Xcode"):
+        xcode_vers = int(lines[0].split()[-1].split(".")[0])
+        if xcode_vers >= 15:
+            ldflags.append("-Wl,-ld_classic")
+
     if os_level == "10.4":
         cflags.append("-DNO_OBJC2_RUNTIME")