SConstruct : Support building with Xcode 15

Xcode 15's new linker now complains when asked to link to the same library multiple times. I've removed the duplicates from the modules required to build a regular Cortex release, though I haven't touched the DCC specific modules. If the existing duplicate library specification turns out to be necessary for other platforms, we could alternately disable the linker warning here with `-no_warn_duplicate_libraries`.

The new linker also complains that the `-single_module` flag is obsolete. `-single_module` became the default behaviour way back in OSX 10.4, so we should be fairly safe to remove it here.

Disabling FMA via `--ffp-contract=off` fixes a test failure with `MeshPrimitiveEvaluator.pointAtUV()` returning an incorrect value in `TestMeshPrimitive.testPlane()`. Curiously, even with `--ffp-contract=off`, this test still fails when run on a virtualized instance of macOS. GitHub's macOS runners are vitualized, so we'll end up skipping this test when we enable macOS CI...

Author: murraystevenson

SConstruct

@@ -1089,6 +1089,14 @@ if env["PLATFORM"] != "win32" :
 		# deprecation of gluBuild2DMipmaps() in OSX 10.9.
 		if osxVersion[0] == 10 and osxVersion[1] > 7 :
 			env.Append( CXXFLAGS = [ "-Wno-unused-local-typedef", "-Wno-deprecated-declarations" ] )
+		clangVersion = subprocess.check_output( [ env["CXX"], "-dumpversion" ], env=env["ENV"], universal_newlines=True ).strip()
+		clangVersion = [ int( v ) for v in clangVersion.split( "." ) ]
+		# Work around Boost issues with Xcode 15 where `std::unary_function` has been removed.
+		if clangVersion >= [ 15, 0, 0 ] :
+			env.Append( CXXFLAGS = [ "-DBOOST_NO_CXX98_FUNCTION_BASE", "-D_HAS_AUTO_PTR_ETC=0" ] )
+		# Disable FMA on arm64 builds to limit floating point discrepancies with x86_64 builds.
+		if platform.machine() == "arm64" :
+			env.Append( CXXFLAGS = [ "-ffp-contract=off" ] )
 
 	elif env["PLATFORM"]=="posix" :
 		if "g++" in os.path.basename( env["CXX"] ) and not "clang++" in os.path.basename( env["CXX"] ) :
@@ -1304,11 +1312,11 @@ if doConfigure :
 		Exit( 1 )
 
 	for line in open( str( boostVersionHeader ) ) :
-		m = re.compile( "^#define BOOST_LIB_VERSION \"(.*)\"\s*$" ).match( line )
+		m = re.compile( r"^#define BOOST_LIB_VERSION \"(.*)\"\s*$" ).match( line )
 		if m  :
 			boostVersion = m.group( 1 )
 		if boostVersion :
-			m = re.compile( "^([0-9]+)_([0-9]+)(?:_([0-9]+)|)$" ).match( boostVersion )
+			m = re.compile( r"^([0-9]+)_([0-9]+)(?:_([0-9]+)|)$" ).match( boostVersion )
 			boostMajorVersion, boostMinorVersion, boostPatchVersion = m.group( 1, 2, 3 )
 			env["BOOST_MAJOR_VERSION"] = boostMajorVersion
 			env["BOOST_MINOR_VERSION"] = boostMinorVersion
@@ -1494,9 +1502,6 @@ pythonModuleEnv = pythonEnv.Clone()
 pythonModuleEnv["SHLIBPREFIX"] = ""
 pythonModuleEnv["SHLIBSUFFIX"] = ".so" if env["PLATFORM"] != "win32" else ".pyd"
 
-if pythonModuleEnv["PLATFORM"]=="darwin" :
-	pythonModuleEnv.Append( SHLINKFLAGS = "-single_module" )
-
 ###########################################################################################
 # An environment for running tests
 ###########################################################################################
@@ -1940,9 +1945,7 @@ if doConfigure :
 		imagePythonModuleEnv.Append( **imageEnvPrepends )
 		imagePythonModuleEnv.Append(
 			LIBS = [
-				os.path.basename( coreEnv.subst( "$INSTALL_LIB_NAME" ) ),
 				os.path.basename( imageEnv.subst( "$INSTALL_LIB_NAME" ) ),
-				os.path.basename( corePythonEnv.subst( "$INSTALL_PYTHONLIB_NAME" ) ),
 			]
 		)
 		imagePythonModule = imagePythonModuleEnv.SharedLibrary( "python/IECoreImage/_IECoreImage", imagePythonSources + imagePythonModuleSources )
@@ -2277,9 +2280,7 @@ if env["WITH_GL"] and doConfigure :
 		glPythonModuleEnv.Append( **glEnvAppends )
 		glPythonModuleEnv.Append(
 			LIBS = [
-				os.path.basename( coreEnv.subst( "$INSTALL_LIB_NAME" ) ),
 				os.path.basename( glEnv.subst( "$INSTALL_LIB_NAME" ) ),
-				os.path.basename( corePythonEnv.subst( "$INSTALL_PYTHONLIB_NAME" ) ),
 				os.path.basename( imageEnv.subst( "$INSTALL_LIB_NAME" ) ),
 				os.path.basename( sceneEnv.subst( "$INSTALL_LIB_NAME" ) ),
 			]

include/IECore/MatrixInterpolator.inl

@@ -130,7 +130,7 @@ struct CubicInterpolator< Imath::Matrix44< T > >
 
 		Imath::Vec3<T> s0( 1 ), s1( 1 ), s2( 1 ), s3( 1 ), sx( 1 );
 		Imath::Vec3<T> h0( 0 ), h1( 0 ), h2( 0 ), h3( 0 ), hx( 0 );
-		Imath::Vec3<T> r0( 0 ), r1( 0 ), r2( 0 ), r3( 0 ), rx( 0 );
+		Imath::Vec3<T> r0( 0 ), r1( 0 ), r2( 0 ), r3( 0 );
 		Imath::Vec3<T> t0( 0 ), t1( 0 ), t2( 0 ), t3( 0 ), tx( 0 );
 
 		extractSHRT(y0, s0, h0, r0, t0);

test/IECore/InterpolatorTest.inl

@@ -429,7 +429,7 @@ void MatrixCubicInterpolatorTest<T>::testSimple()
 	CubicInterpolator< Matrix > interp;
 	CubicInterpolator< Vector > vectorInterp;
 
-	Vector s0( 1, 1, 1 ), h0( 0, 0, 0 ), r0( 0, 0, 0 ), t0( 5, 0, 0 );
+	Vector s0( 1, 1, 1 ), h0( 0, 0, 0 ), t0( 5, 0, 0 );
 	Vector s1( 1, 2, 3 ), h1( 1, 2, 3 ), r1( 0, 1, 0 ), t1( 10, 0, 0 );
 	Vector s2( 0.5, 1.4, 5 ), h2( 2, 3, 4 ), r2( 0, 0.5, 0 ), t2( 20, 0, 0 );
 	Vector s3( 1, 2, 3 ), h3( 1, 2, 3 ), r3( 0, 1, 0 ), t3( 0, 0, 0 );
@@ -492,7 +492,7 @@ void MatrixCubicInterpolatorTest<T>::testTyped()
 	CubicInterpolator< MatrixData > interp;
 	CubicInterpolator< Vector > vectorInterp;
 
-	Vector s0( 1, 1, 1 ), h0( 0, 0, 0 ), r0( 0, 0, 0 ), t0( 5, 0, 0 );
+	Vector s0( 1, 1, 1 ), h0( 0, 0, 0 ), t0( 5, 0, 0 );
 	Vector s1( 1, 2, 3 ), h1( 1, 2, 3 ), r1( 0, 1, 0 ), t1( 10, 0, 0 );
 	Vector s2( 0.5, 1.4, 5 ), h2( 2, 3, 4 ), r2( 0, 0.5, 0 ), t2( 20, 0, 0 );
 	Vector s3( 1, 2, 3 ), h3( 1, 2, 3 ), r3( 0, 1, 0 ), t3( 0, 0, 0 );