Xcode plugin snippet for dumping compiler/linker arguments for the given file(s)

xcodeargdumper.mm

#include <objc/runtime.h>


void dump_compiler_and_linker_args_for_file(NSString *file)
{
	Class PBXReference = NSClassFromString(@"PBXReference");
        if (! PBXReference) return;

	id file_ref = [[PBXReference alloc] initWithPath: file];

	Class PBXProject = NSClassFromString(@"PBXProject");
        if (! PBXProject) return;

	id suggested_targets = [PBXProject performSelector: NSSelectorFromString(@"targetsInAllProjectsForFileReference:justNative:")
	                                        withObject: file_ref
	                                        withObject: nil];

        // If you want to iterate all targets within a project, use smth like this:
        // ----------------- CUT HERE -----------------
        // id open_projects = [PBXProject performSelector: NSSelectorFromString: @"openProjects"];
        // [open_projects enumerateObjectsUsingBlock:^(id project, NSUInteger idx, BOOL *stop)
        // {
        //     id all_targets = [project valueForKey: @"_targets"];
        //     [all_targets enumerateObjectsUsingBlock:^(id target, NSUInteger idx, BOOL *stop)
        //     {
        //         id build_context = [target performSelector: NSSelectorFromString(@"targetBuildContext")];
        //                 // dealing with a context (see below)
        //     }
        // }
        // ----------------- CUT HERE -----------------

        // But that's just a demo, so don't bother
	id target = suggested_targets[0];

	id build_context = [target performSelector: NSSelectorFromString(@"targetBuildContext")];

	NSArray *commands = [build_context performSelector: NSSelectorFromString(@"commands")];
	[commands enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop)
	{
	    NSArray *rule_info = [obj performSelector: NSSelectorFromString(@"ruleInfo")];
	    // Dump compiler arguments for the file
	    if ([[rule_info firstObject] isEqualToString: @"CompileC"]) {
	        /**
	         * Commands can contain build rules for multiple files so 
	         * make sure we got the right one.
	         */
	        NSString *sourcefile_path = [rule_info objectAtIndex: 2];
	        if ( ! [sourcefile_path isEqualToString: file]) {
	            return;
	        }
	        NSString *compiler_path  = [obj valueForKey: @"_commandPath"];
	        NSArray  *compiler_args  = [obj valueForKey: @"_arguments"];

	        NSLog(@"\nCompile file '%@' with command line:\n%@ %@",
	              [sourcefile_path lastPathComponent], [compiler_path lastPathComponent],
	              [compiler_args componentsJoinedByString:@" "]);
	    }
	    // Linker arguments
	    if ([[rule_info firstObject] isEqualToString: @"Ld"]) {
	        /*
	         * Xcode doesn't pass object files (.o) directly to the linker (it uses
	         * a dependency info file instead) so the only thing we can do here is to grab
	         * the linker arguments.
	         */
	        NSString *linker_path  = [obj valueForKey: @"_commandPath"];
	        NSArray *linker_arguments = [obj valueForKey: @"_arguments"];

	        NSLog(@"\nLinker: %@ %@", [linker_path lastPathComponent], [linker_arguments componentsJoinedByString: @" "]);
	    }
	}];
}