Languages: Add support for Objective-C

Add entries in Modules and Modules/Platform to support
Objective-C compiler determination and identification.
Add Modules to check Objective-C compiler flags, source
compilations, program checks, etc...

Use OBJC as the designator of the language, eg:

project(foo OBJC)

Add various tests for Objective-C language features.  Add
tests to preserve C++ handling of .m and .mm files when
OBJC is not a configured language.

Co-Authored-By: Cristian Adam <cristian.adam@gmail.com>

4 files changed, 39 insertions, 0 deletions

diff --git a/Tests/Objective-C/simple-build-test/CMakeLists.txt b/Tests/Objective-C/simple-build-test/CMakeLists.txt
new file mode 100644
index 0000000..5ab46ac
--- /dev/null
+++ b/Tests/Objective-C/simple-build-test/CMakeLists.txt
@@ -0,0 +1,11 @@
+cmake_minimum_required(VERSION 3.15)
+
+set(CMAKE_MACOSX_RPATH OFF)
+
+project(simple-build-test OBJC)
+
+add_library(foo SHARED foo.m)
+target_link_libraries(foo "-framework Foundation")
+
+add_executable(simple-build-test main.m)
+target_link_libraries(simple-build-test "-framework Foundation" foo)
diff --git a/Tests/Objective-C/simple-build-test/foo.h b/Tests/Objective-C/simple-build-test/foo.h
new file mode 100644
index 0000000..b3fb084
--- /dev/null
+++ b/Tests/Objective-C/simple-build-test/foo.h
@@ -0,0 +1,9 @@
+#import <Foundation/Foundation.h>
+
+@interface Foo : NSObject {
+  NSNumber* age;
+}
+
+@property (nonatomic, retain) NSNumber* age;
+
+@end
diff --git a/Tests/Objective-C/simple-build-test/foo.m b/Tests/Objective-C/simple-build-test/foo.m
new file mode 100644
index 0000000..2d452a8
--- /dev/null
+++ b/Tests/Objective-C/simple-build-test/foo.m
@@ -0,0 +1,7 @@
+#import "foo.h"
+
+@implementation Foo
+
+@synthesize age;
+
+@end
diff --git a/Tests/Objective-C/simple-build-test/main.m b/Tests/Objective-C/simple-build-test/main.m
new file mode 100644
index 0000000..970d554
--- /dev/null
+++ b/Tests/Objective-C/simple-build-test/main.m
@@ -0,0 +1,12 @@
+#import <Foundation/Foundation.h>
+#import "foo.h"
+
+int main(int argc, char **argv)
+{
+  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
+  Foo *theFoo = [[Foo alloc] init];
+  theFoo.age = [NSNumber numberWithInt:argc];
+  NSLog(@"%d\n",[theFoo.age intValue]);
+  [pool release];
+  return 0;
+}