https://pspdfkit.com/blog/2016/test-with-asan/

TSAN_OPTIONS.h

//
//  TSAN_OPTIONS.h
//  PSPDFKit
//
//  Copyright © 2016 PSPDFKit GmbH. All rights reserved.
//  Example code licensed under MIT. Enjoy!
//

#if __has_feature(thread_sanitizer)

#include <TargetConditionals.h>

#if TARGET_OS_OSX
// macOS app structure is weird :)
#define TSANSUPPPATH "../Resources/ThreadSanitizerSuppressions.supp"
#else
#define TSANSUPPPATH "ThreadSanitizerSuppressions.supp"
#endif

/*
 See ASAN_OPTIONS for the radar list.
 */

__attribute__((visibility("default"))) __attribute__((no_sanitize_address))
FOUNDATION_EXPORT const char *__tsan_default_options(void);
FOUNDATION_EXPORT const char *__tsan_default_options() {
    /*
     https://github.com/google/sanitizers/wiki
     verbosity: can't hurt :)

     suppressions: You can either specify the full path to the file or the path of the file relative to the location of your executable.
     http://clang.llvm.org/docs/AddressSanitizer.html#suppressing-reports-in-external-libraries
     
     report_thread_leaks=0
     We do not clean up our worker threads in core so this needs to be suppressed.
     
     Optionally useful: halt_on_error=0
     */
    return "verbosity=0:report_thread_leaks=0:halt_on_error=1:suppressions=" TSANSUPPPATH;
}

__attribute__((constructor)) static void PSPDFTSANSettingsPrinter(void) {
    NSLog(@"ThreadSanitizer Enabled. Settings: %s (See TSAN_OPTIONS.h)", __tsan_default_options());
}

#endif