diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 0f1190510f0f8..9f09a7b4e7ebb 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -496,6 +496,11 @@ CUDA Support
 AIX Support
 ^^^^^^^^^^^
 
+- The driver default for the linker flag `-bcdtors` now defaults to `mbr`
+  (instead of `all`) which only extracts static init from archive members which
+  would otherwise be referenced.
+  (See https://www.ibm.com/docs/en/aix/7.2.0?topic=l-ld-command for details).
+
 NetBSD Support
 ^^^^^^^^^^^^^^
 
diff --git a/clang/lib/Driver/ToolChains/AIX.cpp b/clang/lib/Driver/ToolChains/AIX.cpp
index e7f4792ac5bba..e36910f9aaf46 100644
--- a/clang/lib/Driver/ToolChains/AIX.cpp
+++ b/clang/lib/Driver/ToolChains/AIX.cpp
@@ -212,7 +212,7 @@ void aix::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   // language link invocations. This has to come before AddLinkerInputs as the
   // implied option needs to precede any other '-bcdtors' settings or
   // '-bnocdtors' that '-Wl' might forward.
-  CmdArgs.push_back("-bcdtors:all:0:s");
+  CmdArgs.push_back("-bcdtors:mbr:0:s");
 
   if (Args.hasArg(options::OPT_rpath)) {
     for (const auto &bopt : Args.getAllArgValues(options::OPT_b))
diff --git a/clang/test/Driver/aix-ld.c b/clang/test/Driver/aix-ld.c
index 1dae61d91c4e3..bedd224eeca9c 100644
--- a/clang/test/Driver/aix-ld.c
+++ b/clang/test/Driver/aix-ld.c
@@ -353,9 +353,9 @@
 // CHECK-LD32-ARG-ORDER:     "-bpT:0x10000000" "-bpD:0x20000000"
 // CHECK-LD32-ARG-ORDER:     "[[SYSROOT]]/usr/lib{{/|\\\\}}crt0.o"
 // CHECK-LD32-ARG-ORDER:     "[[SYSROOT]]/usr/lib{{/|\\\\}}crti.o"
-// CHECK-LD32-ARG-ORDER:     "-bcdtors:all:0:s"
+// CHECK-LD32-ARG-ORDER:     "-bcdtors:mbr:0:s"
 // CHECK-LD32-ARG-ORDER:     "-bnocdtors"
-// CHECK-LD32-ARG-ORDER-NOT: "-bcdtors:all:0:s"
+// CHECK-LD32-ARG-ORDER-NOT: "-bcdtors:mbr:0:s"
 // CHECK-LD32-ARG-ORDER-NOT: "-lc++"
 // CHECK-LD32-ARG-ORDER-NOT: "-lc++abi"
 // CHECK-LD32-ARG-ORDER:     "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}aix{{/|\\\\}}libclang_rt.builtins-powerpc.a"
@@ -382,9 +382,9 @@
 // CHECK-LD32-CXX-ARG-ORDER:     "-bpT:0x10000000" "-bpD:0x20000000"
 // CHECK-LD32-CXX-ARG-ORDER:     "[[SYSROOT]]/usr/lib{{/|\\\\}}crt0.o"
 // CHECK-LD32-CXX-ARG-ORDER:     "[[SYSROOT]]/usr/lib{{/|\\\\}}crti.o"
-// CHECK-LD32-CXX-ARG-ORDER:     "-bcdtors:all:0:s"
+// CHECK-LD32-CXX-ARG-ORDER:     "-bcdtors:mbr:0:s"
 // CHECK-LD32-CXX-ARG-ORDER:     "-bnocdtors"
-// CHECK-LD32-CXX-ARG-ORDER-NOT: "-bcdtors:all:0:s"
+// CHECK-LD32-CXX-ARG-ORDER-NOT: "-bcdtors:mbr:0:s"
 // CHECK-LD32-CXX-ARG-ORDER:     "-lc++"
 // CHECK-LD32-CXX-ARG-ORDER:     "-lc++abi"
 // CHECK-LD32-CXX-ARG-ORDER:     "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}aix{{/|\\\\}}libclang_rt.builtins-powerpc.a"
diff --git a/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c b/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c
index 9cb313bc7a1fc..7141a553b023f 100644
--- a/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c
+++ b/compiler-rt/lib/profile/InstrProfilingPlatformAIX.c
@@ -181,7 +181,7 @@ void __llvm_profile_register_names_function(void *NamesStart,
 // reference symbols from the profile library (for example when no files were
 // compiled with -fprofile-generate). That's because these symbols are kept
 // alive through references in constructor functions that are always live in the
-// default linking model on AIX (-bcdtors:all). The __start_SECNAME and
+// `-bcdtors:all` linking model on AIX. The __start_SECNAME and
 // __stop_SECNAME symbols are only resolved by the linker when the SECNAME
 // section exists. So for the scenario where the user objects have no such
 // section (i.e. when they are compiled with -fno-profile-generate), we always
diff --git a/compiler-rt/test/profile/instrprof-merge-entry-cover.c b/compiler-rt/test/profile/instrprof-merge-entry-cover.c
index a99458898392f..5856773c09f1b 100644
--- a/compiler-rt/test/profile/instrprof-merge-entry-cover.c
+++ b/compiler-rt/test/profile/instrprof-merge-entry-cover.c
@@ -38,6 +38,7 @@ __attribute__((noinline)) void foo(char c) {
 __attribute__((noinline)) void bar(int M) { g += M; }
 
 int main(int argc, const char *argv[]) {
+  __llvm_profile_test_initialize();
   int i;
   if (argc < 4)
     return 1;
diff --git a/compiler-rt/test/profile/instrprof-merge.c b/compiler-rt/test/profile/instrprof-merge.c
index 8be1016da873e..a94708919daba 100644
--- a/compiler-rt/test/profile/instrprof-merge.c
+++ b/compiler-rt/test/profile/instrprof-merge.c
@@ -37,6 +37,7 @@ void foo(char c) {
 void bar(int M) { g += M; }
 
 int main(int argc, const char *argv[]) {
+  __llvm_profile_test_initialize();
   int i;
   if (argc < 4)
     return 1;
diff --git a/compiler-rt/test/profile/instrprof-write-file-atexit-explicitly.c b/compiler-rt/test/profile/instrprof-write-file-atexit-explicitly.c
index 6923e1d1d55d6..63171cb66ec4c 100644
--- a/compiler-rt/test/profile/instrprof-write-file-atexit-explicitly.c
+++ b/compiler-rt/test/profile/instrprof-write-file-atexit-explicitly.c
@@ -4,10 +4,13 @@
 // RUN: llvm-profdata merge -o %t.profdata %t.profraw
 // RUN: %clang_profuse=%t.profdata -o - -S -emit-llvm %s | FileCheck %s
 
+#include "profile_test.h"
+
 int __llvm_profile_runtime = 0;
 int __llvm_profile_register_write_file_atexit(void);
 void __llvm_profile_set_filename(const char *);
 int main(int argc, const char *argv[]) {
+  __llvm_profile_test_initialize();
   __llvm_profile_register_write_file_atexit();
   // CHECK: br i1 %{{.*}}, label %{{.*}}, label %{{.*}}, !prof ![[PD1:[0-9]+]]
   if (argc < 2)
diff --git a/compiler-rt/test/profile/profile_test.h b/compiler-rt/test/profile/profile_test.h
index 557db99abb51f..b410606a1f2bf 100644
--- a/compiler-rt/test/profile/profile_test.h
+++ b/compiler-rt/test/profile/profile_test.h
@@ -9,4 +9,14 @@
 # define ALIGNED(x) __attribute__((aligned(x)))
 #endif
 
+inline void __llvm_profile_test_initialize() {
+  // This is a no-op on most platforms, but on AIX it forces the linker to
+  // keep the start/stop stub data for the runtime. Normally this data is
+  // referenced by pulling in `__llvm_profile_runtime` from the runtime but
+  // some tests explicitly supress that.
+#ifdef _AIX
+  extern __attribute__((visibility("hidden"))) void *__llvm_profile_keep[];
+  (void)*(void *volatile *)__llvm_profile_keep;
+#endif // _AIX
+}
 #endif  // PROFILE_TEST_H