Fix compiler warnings around ambiguous macro redefinition.

LMK if there's a better way to do this, which doesn't involve requiring
modules.

// FREEBIE

Podfile.lock

@@ -185,7 +185,7 @@ SPEC CHECKSUMS:
   PureLayout: 4d550abe49a94f24c2808b9b95db9131685fe4cd
   Reachability: 33e18b67625424e47b6cde6d202dce689ad7af96
   SAMKeychain: 483e1c9f32984d50ca961e26818a534283b4cd5c
-  SignalServiceKit: cfcc3b067458b74392750ed324fb40d5bcfa2b2a
+  SignalServiceKit: e1fa31c513e47afcb02c9c540d2931fd24d86311
   SocketRocket: dbb1554b8fc288ef8ef370d6285aeca7361be31e
   SQLCipher: 43d12c0eb9c57fb438749618fc3ce0065509a559
   TwistedOakCollapsingFutures: f359b90f203e9ab13dfb92c9ff41842a7fe1cd0c

SignalServiceKit.podspec

@@ -27,6 +27,12 @@ An Objective-C library for communicating with the Signal messaging service.
   s.requires_arc = true
   s.source_files = 'SignalServiceKit/src/**/*.{h,m,mm}'
 
+  # We want to use modules to avoid clobbering CocoaLumberjack macros defined
+  # by other OWS modules which *also* import CocoaLumberjack. But because we
+  # also use Objective-C++, modules are disabled unless we explicitly enable
+  # them
+  s.compiler_flags = "-fcxx-modules"
+
   s.prefix_header_file = 'SignalServiceKit/src/TSPrefix.h'
   s.xcconfig = { 'OTHER_CFLAGS' => '$(inherited) -DSQLITE_HAS_CODEC' }
 

SignalServiceKit/src/TSPrefix.h

@@ -4,15 +4,12 @@
 
 #import <Foundation/Foundation.h>
 
-#import <CocoaLumberjack/CocoaLumberjack.h>
+@import CocoaLumberjack;
-
-#define LOG_LEVEL_DEF sskLogLevel
-#define LOG_ASYNC_ENABLED YES
 
 #ifdef DEBUG
-static const NSUInteger sskLogLevel = DDLogLevelAll;
+static const NSUInteger ddLogLevel = DDLogLevelAll;
 #else
-static const NSUInteger sskLogLevel = DDLogLevelInfo;
+static const NSUInteger ddLogLevel = DDLogLevelInfo;
 #endif
 
 #import "Asserts.h"