[ASan] Move ASan runtime library self-checks to a more appropriate place.

[ygribov]

Summary

This moves ASan runtime library checking to after flag parsing thus reducing copy-paste and also respecting ASAN_OPTIONS (e.g. log_path) when reporting errors.

[samsonov]

LGTM

[ygribov]

Commited in 239018.

lib/asan/asan_linux.cc

 }
 
 static void ReportIncompatibleRT() {
   Report("Your application is linked against incompatible ASan runtimes.\n");
   Die();
 }
 
 void AsanCheckDynamicRTPrereqs() {
+  if (!ASAN_DYNAMIC)
+    return;
+
   // Ensure that dynamic RT is the first DSO in the list
   const char *first_dso_name = 0;
   dl_iterate_phdr(FindFirstDSOCallback, &first_dso_name);
   if (first_dso_name && !IsDynamicRTName(first_dso_name)) {
     Report("ASan runtime does not come first in initial library list; "
            "you should either link runtime to your application or "
            "manually preload it with LD_PRELOAD.\n");
     Die();

lib/asan/asan_rtl.cc

static void AsanInitInternal() {
   SanitizerToolName = "AddressSanitizer";
   CHECK(!asan_init_is_running && "ASan init calls itself!");
   asan_init_is_running = true;
 
   // Initialize flags. This must be done early, because most of the
   // initialization steps look at flags().
   InitializeFlags();
 
+  AsanCheckIncompatibleRT();
+  AsanCheckDynamicRTPrereqs();
+
   SetCanPoisonMemory(flags()->poison_heap);
   SetMallocContextSize(common_flags()->malloc_context_size);
 
   InitializeHighMemEnd();
 
   // Make sure we are not statically linked.
   AsanDoesNotSupportStaticLinkage();
 

 // Initialize as requested from some part of ASan runtime library (interceptors,
 // allocator, etc).
 void AsanInitFromRtl() {
   AsanInitInternal();
 }
 
 #if ASAN_DYNAMIC
 // Initialize runtime in case it's LD_PRELOAD-ed into unsanitized executable
-// (and thus normal initializer from .preinit_array haven't run).
+// (and thus normal initializers from .preinit_array or modules haven't run).
 
 class AsanInitializer {
 public:  // NOLINT
   AsanInitializer() {
-    AsanCheckIncompatibleRT();
-    AsanCheckDynamicRTPrereqs();
     AsanInitFromRtl();
   }
 };
 
 static AsanInitializer asan_initializer;
 #endif  // ASAN_DYNAMIC
 
 }  // namespace __asan

 
 void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
   SetUserDieCallback(callback);
 }
 
 // Initialize as requested from instrumented application code.
 // We use this call as a trigger to wake up ASan from deactivated state.
 void __asan_init() {
-  AsanCheckIncompatibleRT();
   AsanActivate();
   AsanInitInternal();
 }