diff --git a/compiler-rt/lib/asan/asan_allocator.h b/compiler-rt/lib/asan/asan_allocator.h
index f817ce352ee2..7e363c35f396 100644
--- a/compiler-rt/lib/asan/asan_allocator.h
+++ b/compiler-rt/lib/asan/asan_allocator.h
@@ -102,10 +102,13 @@ struct AsanThreadLocalMallocStorage {
   void CommitBack();
 };
 
+SANITIZER_INTERFACE_ATTRIBUTE
 void *asan_memalign(uptr alignment, uptr size, StackTrace *stack,
                     AllocType alloc_type);
+SANITIZER_INTERFACE_ATTRIBUTE
 void asan_free(void *ptr, StackTrace *stack, AllocType alloc_type);
 
+SANITIZER_INTERFACE_ATTRIBUTE
 void *asan_malloc(uptr size, StackTrace *stack);
 void *asan_calloc(uptr nmemb, uptr size, StackTrace *stack);
 void *asan_realloc(void *p, uptr size, StackTrace *stack);
@@ -114,6 +117,7 @@ void *asan_pvalloc(uptr size, StackTrace *stack);
 
 int asan_posix_memalign(void **memptr, uptr alignment, uptr size,
                           StackTrace *stack);
+SANITIZER_INTERFACE_ATTRIBUTE
 uptr asan_malloc_usable_size(void *ptr, StackTrace *stack);
 
 uptr asan_mz_size(const void *ptr);
diff --git a/compiler-rt/lib/asan/asan_allocator2.cc b/compiler-rt/lib/asan/asan_allocator2.cc
index 63d6adaece31..97c992970611 100644
--- a/compiler-rt/lib/asan/asan_allocator2.cc
+++ b/compiler-rt/lib/asan/asan_allocator2.cc
@@ -812,12 +812,12 @@ uptr __asan_get_allocated_size(const void *p) {
 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
 // Provide default (no-op) implementation of malloc hooks.
 extern "C" {
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 void __asan_malloc_hook(void *ptr, uptr size) {
   (void)ptr;
   (void)size;
 }
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 void __asan_free_hook(void *ptr) {
   (void)ptr;
 }
diff --git a/compiler-rt/lib/asan/asan_interface_internal.h b/compiler-rt/lib/asan/asan_interface_internal.h
index 24f76253bccd..48ff05d88936 100644
--- a/compiler-rt/lib/asan/asan_interface_internal.h
+++ b/compiler-rt/lib/asan/asan_interface_internal.h
@@ -30,7 +30,7 @@ extern "C" {
   // v2=>v3: stack frame description (created by the compiler)
   //         contains the function PC as the 3-rd field (see
   //         DescribeAddressIfStack).
-  void __asan_init_v3() SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE void __asan_init_v3();
   #define __asan_init __asan_init_v3
 
   // This structure describes an instrumented global variable.
@@ -46,96 +46,90 @@ extern "C" {
 
   // These two functions should be called by the instrumented code.
   // 'globals' is an array of structures describing 'n' globals.
-  void __asan_register_globals(__asan_global *globals, uptr n)
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  void __asan_unregister_globals(__asan_global *globals, uptr n)
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_register_globals(__asan_global *globals, uptr n);
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_unregister_globals(__asan_global *globals, uptr n);
 
   // These two functions should be called before and after dynamic initializers
   // of a single module run, respectively.
-  void __asan_before_dynamic_init(const char *module_name)
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  void __asan_after_dynamic_init()
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_before_dynamic_init(const char *module_name);
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_after_dynamic_init();
 
   // These two functions are used by the instrumented code in the
   // use-after-return mode. __asan_stack_malloc allocates size bytes of
   // fake stack and __asan_stack_free poisons it. real_stack is a pointer to
   // the real stack region.
-  uptr __asan_stack_malloc(uptr size, uptr real_stack)
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  void __asan_stack_free(uptr ptr, uptr size, uptr real_stack)
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  uptr __asan_stack_malloc(uptr size, uptr real_stack);
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_stack_free(uptr ptr, uptr size, uptr real_stack);
 
   // These two functions are used by instrumented code in the
   // use-after-scope mode. They mark memory for local variables as
   // unaddressable when they leave scope and addressable before the
   // function exits.
-  void __asan_poison_stack_memory(uptr addr, uptr size)
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  void __asan_unpoison_stack_memory(uptr addr, uptr size)
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_poison_stack_memory(uptr addr, uptr size);
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_unpoison_stack_memory(uptr addr, uptr size);
 
   // Performs cleanup before a NoReturn function. Must be called before things
   // like _exit and execl to avoid false positives on stack.
-  void __asan_handle_no_return() SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE void __asan_handle_no_return();
 
-  void __asan_poison_memory_region(void const volatile *addr, uptr size)
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  void __asan_unpoison_memory_region(void const volatile *addr, uptr size)
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_poison_memory_region(void const volatile *addr, uptr size);
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_unpoison_memory_region(void const volatile *addr, uptr size);
 
-  bool __asan_address_is_poisoned(void const volatile *addr)
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  bool __asan_address_is_poisoned(void const volatile *addr);
 
-  uptr __asan_region_is_poisoned(uptr beg, uptr size)
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  uptr __asan_region_is_poisoned(uptr beg, uptr size);
 
-  void __asan_describe_address(uptr addr)
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_describe_address(uptr addr);
 
+  SANITIZER_INTERFACE_ATTRIBUTE
   void __asan_report_error(uptr pc, uptr bp, uptr sp,
-                           uptr addr, bool is_write, uptr access_size)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+                           uptr addr, bool is_write, uptr access_size);
 
-  int __asan_set_error_exit_code(int exit_code)
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  void __asan_set_death_callback(void (*callback)(void))
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  void __asan_set_error_report_callback(void (*callback)(const char*))
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  int __asan_set_error_exit_code(int exit_code);
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_set_death_callback(void (*callback)(void));
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __asan_set_error_report_callback(void (*callback)(const char*));
 
-  /* OPTIONAL */ void __asan_on_error()
-      SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+  /* OPTIONAL */ void __asan_on_error();
 
+  SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
   /* OPTIONAL */ bool __asan_symbolize(const void *pc, char *out_buffer,
-                                       int out_size)
-      SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE;
+                                       int out_size);
 
-  uptr __asan_get_estimated_allocated_size(uptr size)
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  bool __asan_get_ownership(const void *p)
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  uptr __asan_get_allocated_size(const void *p)
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  uptr __asan_get_current_allocated_bytes()
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  uptr __asan_get_heap_size()
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  uptr __asan_get_free_bytes()
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  uptr __asan_get_unmapped_bytes()
-      SANITIZER_INTERFACE_ATTRIBUTE;
-  void __asan_print_accumulated_stats()
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  uptr __asan_get_estimated_allocated_size(uptr size);
 
-  /* OPTIONAL */ const char* __asan_default_options()
-      SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE bool __asan_get_ownership(const void *p);
+  SANITIZER_INTERFACE_ATTRIBUTE uptr __asan_get_allocated_size(const void *p);
+  SANITIZER_INTERFACE_ATTRIBUTE uptr __asan_get_current_allocated_bytes();
+  SANITIZER_INTERFACE_ATTRIBUTE uptr __asan_get_heap_size();
+  SANITIZER_INTERFACE_ATTRIBUTE uptr __asan_get_free_bytes();
+  SANITIZER_INTERFACE_ATTRIBUTE uptr __asan_get_unmapped_bytes();
+  SANITIZER_INTERFACE_ATTRIBUTE void __asan_print_accumulated_stats();
 
-  /* OPTIONAL */ void __asan_malloc_hook(void *ptr, uptr size)
-      SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE;
-  /* OPTIONAL */ void __asan_free_hook(void *ptr)
-      SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+  /* OPTIONAL */ const char* __asan_default_options();
+
+  SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+  /* OPTIONAL */ void __asan_malloc_hook(void *ptr, uptr size);
+  SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+  /* OPTIONAL */ void __asan_free_hook(void *ptr);
 }  // extern "C"
 
 #endif  // ASAN_INTERFACE_INTERNAL_H
diff --git a/compiler-rt/lib/asan/asan_report.cc b/compiler-rt/lib/asan/asan_report.cc
index 9c46b49e47f6..f5c67f1b9497 100644
--- a/compiler-rt/lib/asan/asan_report.cc
+++ b/compiler-rt/lib/asan/asan_report.cc
@@ -759,6 +759,6 @@ void __asan_describe_address(uptr addr) {
 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
 // Provide default implementation of __asan_on_error that does nothing
 // and may be overriden by user.
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE NOINLINE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE NOINLINE
 void __asan_on_error() {}
 #endif
diff --git a/compiler-rt/lib/asan/asan_rtl.cc b/compiler-rt/lib/asan/asan_rtl.cc
index 1459374ff03f..faedcdfa58ed 100644
--- a/compiler-rt/lib/asan/asan_rtl.cc
+++ b/compiler-rt/lib/asan/asan_rtl.cc
@@ -395,7 +395,7 @@ using namespace __asan;  // NOLINT
 
 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
 extern "C" {
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 const char* __asan_default_options() { return ""; }
 }  // extern "C"
 #endif
diff --git a/compiler-rt/lib/asan/asan_stack.cc b/compiler-rt/lib/asan/asan_stack.cc
index 21dae7df096a..06f48eaef373 100644
--- a/compiler-rt/lib/asan/asan_stack.cc
+++ b/compiler-rt/lib/asan/asan_stack.cc
@@ -37,7 +37,7 @@ void PrintStack(StackTrace *stack) {
 // and may be overriden by user if he wants to use his own symbolization.
 // ASan on Windows has its own implementation of this.
 #if !SANITIZER_WINDOWS && !SANITIZER_SUPPORTS_WEAK_HOOKS
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE NOINLINE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE NOINLINE
 bool __asan_symbolize(const void *pc, char *out_buffer, int out_size) {
   return false;
 }
diff --git a/compiler-rt/lib/lsan/lsan_common.cc b/compiler-rt/lib/lsan/lsan_common.cc
index 265b1ce333ec..8a05b0c822a0 100644
--- a/compiler-rt/lib/lsan/lsan_common.cc
+++ b/compiler-rt/lib/lsan/lsan_common.cc
@@ -556,7 +556,7 @@ void __lsan_do_leak_check() {
 }
 
 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 int __lsan_is_turned_off() {
   return 0;
 }
diff --git a/compiler-rt/lib/lsan/lsan_common.h b/compiler-rt/lib/lsan/lsan_common.h
index 926dea80f153..971f7486cb3d 100644
--- a/compiler-rt/lib/lsan/lsan_common.h
+++ b/compiler-rt/lib/lsan/lsan_common.h
@@ -166,10 +166,11 @@ class LsanMetadata {
 }  // namespace __lsan
 
 extern "C" {
-int __lsan_is_turned_off() SANITIZER_WEAK_ATTRIBUTE
-    SANITIZER_INTERFACE_ATTRIBUTE;
-const char *__lsan_default_suppressions() SANITIZER_WEAK_ATTRIBUTE
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+int __lsan_is_turned_off();
+
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+const char *__lsan_default_suppressions();
 }  // extern "C"
 
 #endif  // LSAN_COMMON_H
diff --git a/compiler-rt/lib/msan/msan.cc b/compiler-rt/lib/msan/msan.cc
index eb53e7b554c9..6bc5d5bec979 100644
--- a/compiler-rt/lib/msan/msan.cc
+++ b/compiler-rt/lib/msan/msan.cc
@@ -501,7 +501,7 @@ void __sanitizer_unaligned_store64(uu64 *p, u64 x) {
 
 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
 extern "C" {
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 const char* __msan_default_options() { return ""; }
 }  // extern "C"
 #endif
diff --git a/compiler-rt/lib/msan/msan_interface_internal.h b/compiler-rt/lib/msan/msan_interface_internal.h
index 5d643e8627a8..c8f51138d047 100644
--- a/compiler-rt/lib/msan/msan_interface_internal.h
+++ b/compiler-rt/lib/msan/msan_interface_internal.h
@@ -88,7 +88,7 @@ void __msan_set_keep_going(int keep_going);
 SANITIZER_INTERFACE_ATTRIBUTE
 int __msan_set_poison_in_malloc(int do_poison);
 
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 /* OPTIONAL */ const char* __msan_default_options();
 
 // For testing.
@@ -163,10 +163,10 @@ uptr __msan_get_free_bytes();
 SANITIZER_INTERFACE_ATTRIBUTE
 uptr __msan_get_unmapped_bytes();
 
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 /* OPTIONAL */ void __msan_malloc_hook(void *ptr, uptr size);
 
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 /* OPTIONAL */ void __msan_free_hook(void *ptr);
 }  // extern "C"
 
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common.h b/compiler-rt/lib/sanitizer_common/sanitizer_common.h
index 4288a9a78a57..1c456d0760e7 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common.h
@@ -153,7 +153,7 @@ void SortArray(uptr *array, uptr size);
 // Exit
 void NORETURN Abort();
 void NORETURN Die();
-void NORETURN SANITIZER_INTERFACE_ATTRIBUTE
+void NORETURN
 CheckFailed(const char *file, int line, const char *cond, u64 v1, u64 v2);
 
 // Set the name of the current thread to 'name', return true on succees.
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h b/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h
index 3e2c6d1f044a..60e076f77900 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h
@@ -15,9 +15,10 @@
 
 #include "sanitizer_platform.h"
 
+// Only use SANITIZER_*ATTRIBUTE* before the function return type!
 #if SANITIZER_WINDOWS
-// FIXME find out what we need on Windows. __declspec(dllexport) ?
-# define SANITIZER_INTERFACE_ATTRIBUTE
+# define SANITIZER_INTERFACE_ATTRIBUTE __declspec(dllexport)
+// FIXME find out what we need on Windows, if anything.
 # define SANITIZER_WEAK_ATTRIBUTE
 #elif defined(SANITIZER_GO)
 # define SANITIZER_INTERFACE_ATTRIBUTE
@@ -82,25 +83,25 @@ typedef u64  OFF64_T;
 
 extern "C" {
   // Tell the tools to write their reports to "path.<pid>" instead of stderr.
-  void __sanitizer_set_report_path(const char *path)
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __sanitizer_set_report_path(const char *path);
 
   // Tell the tools to write their reports to given file descriptor instead of
   // stderr.
-  void __sanitizer_set_report_fd(int fd)
-      SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __sanitizer_set_report_fd(int fd);
 
   // Notify the tools that the sandbox is going to be turned on. The reserved
   // parameter will be used in the future to hold a structure with functions
   // that the tools may call to bypass the sandbox.
-  void __sanitizer_sandbox_on_notify(void *reserved)
-      SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+  void __sanitizer_sandbox_on_notify(void *reserved);
 
   // This function is called by the tool when it has just finished reporting
   // an error. 'error_summary' is a one-line string that summarizes
   // the error message. This function can be overridden by the client.
-  void __sanitizer_report_error_summary(const char *error_summary)
-      SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE;
+  SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+  void __sanitizer_report_error_summary(const char *error_summary);
 }  // extern "C"
 
 
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc b/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc
index 57aae1ade2b9..7dcd69c115de 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc
@@ -250,7 +250,7 @@ const char *GetEnv(const char *name) {
 }
 
 extern "C" {
-  extern void *__libc_stack_end SANITIZER_WEAK_ATTRIBUTE;
+  SANITIZER_WEAK_ATTRIBUTE extern void *__libc_stack_end;
 }
 
 #if !SANITIZER_GO
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_printf.cc b/compiler-rt/lib/sanitizer_common/sanitizer_printf.cc
index 2d8c04a38aae..e2331291b1e6 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_printf.cc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_printf.cc
@@ -197,7 +197,7 @@ void SetPrintfAndReportCallback(void (*callback)(const char *)) {
 
 #if SANITIZER_SUPPORTS_WEAK_HOOKS
 // Can be overriden in frontend.
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 void OnPrint(const char *str);
 #endif
 
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.h b/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.h
index 76d52bd26f07..187fb032d49b 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.h
@@ -60,8 +60,10 @@ struct StackTrace {
   static uptr GetCurrentPc();
   static uptr GetPreviousInstructionPc(uptr pc);
 
+  SANITIZER_INTERFACE_ATTRIBUTE
   static uptr CompressStack(StackTrace *stack,
                             u32 *compressed, uptr size);
+  SANITIZER_INTERFACE_ATTRIBUTE
   static void UncompressStack(StackTrace *stack,
                               u32 *compressed, uptr size);
 };
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h
index 5a15a3fe5715..3f3149cb7a34 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h
@@ -43,7 +43,7 @@ struct AddressInfo {
     internal_memset(this, 0, sizeof(AddressInfo));
   }
   // Deletes all strings and sets all fields to zero.
-  void Clear() SANITIZER_WEAK_ATTRIBUTE;
+  SANITIZER_WEAK_ATTRIBUTE void Clear();
 
   void FillAddressAndModuleInfo(uptr addr, const char *mod_name,
                                 uptr mod_offset) {
@@ -66,8 +66,8 @@ struct DataInfo {
 // for a given address (in all inlined functions). Returns the number
 // of descriptions actually filled.
 // This function should NOT be called from two threads simultaneously.
-uptr SymbolizeCode(uptr address, AddressInfo *frames, uptr max_frames)
-    SANITIZER_WEAK_ATTRIBUTE;
+SANITIZER_WEAK_ATTRIBUTE
+uptr SymbolizeCode(uptr address, AddressInfo *frames, uptr max_frames);
 bool SymbolizeData(uptr address, DataInfo *info);
 
 bool IsSymbolizerAvailable();
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_itanium.cc b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_itanium.cc
index 93a26e634cff..8ad6d67df47d 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_itanium.cc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_itanium.cc
@@ -22,9 +22,9 @@
 // because we do not require a C++ ABI library to be linked to a program
 // using sanitizers; if it's not present, we'll just use the mangled name.
 namespace __cxxabiv1 {
+  SANITIZER_WEAK_ATTRIBUTE
   extern "C" char *__cxa_demangle(const char *mangled, char *buffer,
-                                  size_t *length, int *status)
-    SANITIZER_WEAK_ATTRIBUTE;
+                                  size_t *length, int *status);
 }
 
 const char *__sanitizer::DemangleCXXABI(const char *name) {
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cc b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cc
index 4f0b2ab2a346..125dd99fb186 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cc
@@ -182,15 +182,15 @@ static LowLevelAllocator symbolizer_allocator;  // Linker initialized.
 
 #if SANITIZER_SUPPORTS_WEAK_HOOKS
 extern "C" {
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 bool __sanitizer_symbolize_code(const char *ModuleName, u64 ModuleOffset,
                                 char *Buffer, int MaxLength);
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 bool __sanitizer_symbolize_data(const char *ModuleName, u64 ModuleOffset,
                                 char *Buffer, int MaxLength);
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 void __sanitizer_symbolize_flush();
-SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 int __sanitizer_symbolize_demangle(const char *Name, char *Buffer,
                                    int MaxLength);
 }  // extern "C"
diff --git a/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc b/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc
index 85bf30f6c218..7a746f77cc12 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc
+++ b/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc
@@ -368,29 +368,29 @@ extern "C" void __tsan_setjmp(uptr sp, uptr mangled_sp) {
 }
 
 // Not called.  Merely to satisfy TSAN_INTERCEPT().
-extern "C" int __interceptor_setjmp(void *env)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+extern "C" int __interceptor_setjmp(void *env);
 extern "C" int __interceptor_setjmp(void *env) {
   CHECK(0);
   return 0;
 }
 
-extern "C" int __interceptor__setjmp(void *env)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+extern "C" int __interceptor__setjmp(void *env);
 extern "C" int __interceptor__setjmp(void *env) {
   CHECK(0);
   return 0;
 }
 
-extern "C" int __interceptor_sigsetjmp(void *env)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+extern "C" int __interceptor_sigsetjmp(void *env);
 extern "C" int __interceptor_sigsetjmp(void *env) {
   CHECK(0);
   return 0;
 }
 
-extern "C" int __interceptor___sigsetjmp(void *env)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+extern "C" int __interceptor___sigsetjmp(void *env);
 extern "C" int __interceptor___sigsetjmp(void *env) {
   CHECK(0);
   return 0;
@@ -502,26 +502,26 @@ TSAN_INTERCEPTOR(uptr, malloc_usable_size, void *p) {
   invoke_malloc_hook(p, size);  \
   return p;
 
-void *operator new(__sanitizer::uptr size)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+void *operator new(__sanitizer::uptr size);
 void *operator new(__sanitizer::uptr size) {
   OPERATOR_NEW_BODY(_Znwm);
 }
 
-void *operator new[](__sanitizer::uptr size)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+void *operator new[](__sanitizer::uptr size);
 void *operator new[](__sanitizer::uptr size) {
   OPERATOR_NEW_BODY(_Znam);
 }
 
-void *operator new(__sanitizer::uptr size, std::nothrow_t const&)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+void *operator new(__sanitizer::uptr size, std::nothrow_t const&);
 void *operator new(__sanitizer::uptr size, std::nothrow_t const&) {
   OPERATOR_NEW_BODY(_ZnwmRKSt9nothrow_t);
 }
 
-void *operator new[](__sanitizer::uptr size, std::nothrow_t const&)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+void *operator new[](__sanitizer::uptr size, std::nothrow_t const&);
 void *operator new[](__sanitizer::uptr size, std::nothrow_t const&) {
   OPERATOR_NEW_BODY(_ZnamRKSt9nothrow_t);
 }
@@ -534,26 +534,26 @@ void *operator new[](__sanitizer::uptr size, std::nothrow_t const&) {
   SCOPED_INTERCEPTOR_RAW(mangled_name, ptr);  \
   user_free(thr, pc, ptr);
 
-void operator delete(void *ptr)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+void operator delete(void *ptr);
 void operator delete(void *ptr) {
   OPERATOR_DELETE_BODY(_ZdlPv);
 }
 
-void operator delete[](void *ptr)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+void operator delete[](void *ptr);
 void operator delete[](void *ptr) {
   OPERATOR_DELETE_BODY(_ZdlPvRKSt9nothrow_t);
 }
 
-void operator delete(void *ptr, std::nothrow_t const&)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+void operator delete(void *ptr, std::nothrow_t const&);
 void operator delete(void *ptr, std::nothrow_t const&) {
   OPERATOR_DELETE_BODY(_ZdaPv);
 }
 
-void operator delete[](void *ptr, std::nothrow_t const&)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+void operator delete[](void *ptr, std::nothrow_t const&);
 void operator delete[](void *ptr, std::nothrow_t const&) {
   OPERATOR_DELETE_BODY(_ZdaPvRKSt9nothrow_t);
 }
diff --git a/compiler-rt/lib/tsan/rtl/tsan_interface.cc b/compiler-rt/lib/tsan/rtl/tsan_interface.cc
index b4cdb3a4f044..9de3808e79ff 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_interface.cc
+++ b/compiler-rt/lib/tsan/rtl/tsan_interface.cc
@@ -69,18 +69,24 @@ void __tsan_unaligned_write8(uu64 *addr, u64 v) {
 }
 
 extern "C" {
+SANITIZER_INTERFACE_ATTRIBUTE
 uint16_t __sanitizer_unaligned_load16(void *addr)
-    ALIAS("__tsan_unaligned_read2") SANITIZER_INTERFACE_ATTRIBUTE;
+    ALIAS("__tsan_unaligned_read2");
+SANITIZER_INTERFACE_ATTRIBUTE
 uint32_t __sanitizer_unaligned_load32(void *addr)
-    ALIAS("__tsan_unaligned_read4") SANITIZER_INTERFACE_ATTRIBUTE;
+    ALIAS("__tsan_unaligned_read4");
+SANITIZER_INTERFACE_ATTRIBUTE
 uint64_t __sanitizer_unaligned_load64(void *addr)
-    ALIAS("__tsan_unaligned_read8") SANITIZER_INTERFACE_ATTRIBUTE;
+    ALIAS("__tsan_unaligned_read8");
+SANITIZER_INTERFACE_ATTRIBUTE
 void __sanitizer_unaligned_store16(void *addr, uint16_t v)
-    ALIAS("__tsan_unaligned_write2") SANITIZER_INTERFACE_ATTRIBUTE;
+    ALIAS("__tsan_unaligned_write2");
+SANITIZER_INTERFACE_ATTRIBUTE
 void __sanitizer_unaligned_store32(void *addr, uint32_t v)
-    ALIAS("__tsan_unaligned_write4") SANITIZER_INTERFACE_ATTRIBUTE;
+    ALIAS("__tsan_unaligned_write4");
+SANITIZER_INTERFACE_ATTRIBUTE
 void __sanitizer_unaligned_store64(void *addr, uint64_t v)
-    ALIAS("__tsan_unaligned_write8") SANITIZER_INTERFACE_ATTRIBUTE;
+    ALIAS("__tsan_unaligned_write8");
 }
 
 void __tsan_acquire(void *addr) {
diff --git a/compiler-rt/lib/tsan/rtl/tsan_interface.h b/compiler-rt/lib/tsan/rtl/tsan_interface.h
index eb75400ec668..70450697d480 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_interface.h
+++ b/compiler-rt/lib/tsan/rtl/tsan_interface.h
@@ -27,38 +27,38 @@ extern "C" {
 
 // This function should be called at the very beginning of the process,
 // before any instrumented code is executed and before any call to malloc.
-void __tsan_init() SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_init();
 
-void __tsan_read1(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_read2(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_read4(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_read8(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_read16(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_read1(void *addr);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_read2(void *addr);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_read4(void *addr);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_read8(void *addr);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_read16(void *addr);
 
-void __tsan_write1(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_write2(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_write4(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_write8(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_write16(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_write1(void *addr);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_write2(void *addr);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_write4(void *addr);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_write8(void *addr);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_write16(void *addr);
 
-u16 __tsan_unaligned_read2(const uu16 *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-u32 __tsan_unaligned_read4(const uu32 *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-u64 __tsan_unaligned_read8(const uu64 *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_unaligned_write2(uu16 *addr, u16 v) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_unaligned_write4(uu32 *addr, u32 v) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_unaligned_write8(uu64 *addr, u64 v) SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE u16 __tsan_unaligned_read2(const uu16 *addr);
+SANITIZER_INTERFACE_ATTRIBUTE u32 __tsan_unaligned_read4(const uu32 *addr);
+SANITIZER_INTERFACE_ATTRIBUTE u64 __tsan_unaligned_read8(const uu64 *addr);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_unaligned_write2(uu16 *addr, u16 v);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_unaligned_write4(uu32 *addr, u32 v);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_unaligned_write8(uu64 *addr, u64 v);
 
-void __tsan_vptr_read(void **vptr_p) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_vptr_update(void **vptr_p, void *new_val)
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_vptr_read(void **vptr_p);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __tsan_vptr_update(void **vptr_p, void *new_val);
 
-void __tsan_func_entry(void *call_pc) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_func_exit() SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_func_entry(void *call_pc);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_func_exit();
 
-void __tsan_read_range(void *addr, unsigned long size)  // NOLINT
-    SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_write_range(void *addr, unsigned long size)  // NOLINT
-    SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE
+void __tsan_read_range(void *addr, unsigned long size);  // NOLINT
+SANITIZER_INTERFACE_ATTRIBUTE
+void __tsan_write_range(void *addr, unsigned long size);  // NOLINT
 
 #ifdef __cplusplus
 }  // extern "C"
diff --git a/compiler-rt/lib/tsan/rtl/tsan_interface_ann.h b/compiler-rt/lib/tsan/rtl/tsan_interface_ann.h
index 8e45328e7ec1..963bcc55afaa 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_interface_ann.h
+++ b/compiler-rt/lib/tsan/rtl/tsan_interface_ann.h
@@ -23,8 +23,8 @@
 extern "C" {
 #endif
 
-void __tsan_acquire(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
-void __tsan_release(void *addr) SANITIZER_INTERFACE_ATTRIBUTE;
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_acquire(void *addr);
+SANITIZER_INTERFACE_ATTRIBUTE void __tsan_release(void *addr);
 
 #ifdef __cplusplus
 }  // extern "C"