diff --git a/clang/test/Analysis/padding_c.c b/clang/test/Analysis/padding_c.c
--- a/clang/test/Analysis/padding_c.c
+++ b/clang/test/Analysis/padding_c.c
@@ -1,8 +1,10 @@
-// RUN: %clang_analyze_cc1 -verify %s \
+// FIXME -Wno-aix-compat added temporarily while the diagnostic is being
+// refined.
+// RUN: %clang_analyze_cc1 -verify -Wno-aix-compat %s \
 // RUN:   -analyzer-checker=optin.performance \
 // RUN:   -analyzer-config optin.performance.Padding:AllowedPad=2
 
-// RUN: not %clang_analyze_cc1 -verify %s \
+// RUN: not %clang_analyze_cc1 -verify -Wno-aix-compat %s \
 // RUN:   -analyzer-checker=core \
 // RUN:   -analyzer-checker=optin.performance.Padding \
 // RUN:   -analyzer-config optin.performance.Padding:AllowedPad=-10 \
diff --git a/clang/test/Analysis/padding_cpp.cpp b/clang/test/Analysis/padding_cpp.cpp
--- a/clang/test/Analysis/padding_cpp.cpp
+++ b/clang/test/Analysis/padding_cpp.cpp
@@ -1,4 +1,6 @@
-// RUN: %clang_analyze_cc1 -std=c++14 -analyzer-checker=optin.performance -analyzer-config optin.performance.Padding:AllowedPad=2 -verify %s
+// FIXME -Wno-aix-compat added temporarily while the diagnostic is being
+// refined.
+// RUN: %clang_analyze_cc1 -std=c++14 -analyzer-checker=optin.performance -analyzer-config optin.performance.Padding:AllowedPad=2 -verify -Wno-aix-compat %s
 
 // Make sure that the C cases still work fine, even when compiled as C++.
 #include "padding_c.c"
diff --git a/clang/test/CXX/drs/dr6xx.cpp b/clang/test/CXX/drs/dr6xx.cpp
--- a/clang/test/CXX/drs/dr6xx.cpp
+++ b/clang/test/CXX/drs/dr6xx.cpp
@@ -1,8 +1,10 @@
-// RUN: %clang_cc1 -std=c++98 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors -fno-spell-checking
-// RUN: %clang_cc1 -std=c++11 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors -fno-spell-checking
-// RUN: %clang_cc1 -std=c++14 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors -fno-spell-checking
-// RUN: %clang_cc1 -std=c++17 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors -fno-spell-checking
-// RUN: %clang_cc1 -std=c++20 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors -fno-spell-checking
+// FIXME -Wno-aix-compat added temporarily while the diagnostic is being
+// refined.
+// RUN: %clang_cc1 -std=c++98 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors -fno-spell-checking -Wno-aix-compat
+// RUN: %clang_cc1 -std=c++11 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors -fno-spell-checking -Wno-aix-compat
+// RUN: %clang_cc1 -std=c++14 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors -fno-spell-checking -Wno-aix-compat
+// RUN: %clang_cc1 -std=c++17 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors -fno-spell-checking -Wno-aix-compat
+// RUN: %clang_cc1 -std=c++20 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors -fno-spell-checking -Wno-aix-compat
 
 namespace std {
   struct type_info {};
diff --git a/clang/test/SemaTemplate/instantiate-attr.cpp b/clang/test/SemaTemplate/instantiate-attr.cpp
--- a/clang/test/SemaTemplate/instantiate-attr.cpp
+++ b/clang/test/SemaTemplate/instantiate-attr.cpp
@@ -1,4 +1,7 @@
-// RUN: %clang_cc1 -fsyntax-only -verify %s
+// FIXME -Wno-aix-compat added temporarily while the diagnostic is being
+// refined.
+
+// RUN: %clang_cc1 -fsyntax-only -verify -Wno-aix-compat %s
 // expected-no-diagnostics
 template <typename T>
 struct A {