diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -298,6 +298,17 @@
   JustMyCode feature. Note, you may need to manually add ``/JMC`` as additional
   compile options in the Visual Studio since it currently assumes clang-cl does not support ``/JMC``.
 
+AIX Support
+-----------
+
+- The driver no longer adds ``-mignore-xcoff-visibility`` by default for AIX
+  targets when no other visibility command-line options are in effect, as
+  ignoring hidden visibility can silently have undesirable side effects (e.g
+  when libraries depend on visibility to hide non-ABI facing entities). The
+  ``-mignore-xcoff-visibility`` option can be manually specified on the
+  command-line to recover the previous behavior if desired.
+
+
 C Language Changes in Clang
 ---------------------------
 
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -5922,9 +5922,7 @@
   MarshallingInfoInt<CodeGenOpts<"SSPBufferSize">, "8">;
 def fvisibility : Separate<["-"], "fvisibility">,
   HelpText<"Default type and symbol visibility">,
-  MarshallingInfoVisibility<LangOpts<"ValueVisibilityMode">, "DefaultVisibility">,
-  // Always emitting because of the relation to `-mignore-xcoff-visibility`.
-  AlwaysEmit;
+  MarshallingInfoVisibility<LangOpts<"ValueVisibilityMode">, "DefaultVisibility">;
 def ftype_visibility : Separate<["-"], "ftype-visibility">,
   HelpText<"Default type visibility">,
   MarshallingInfoVisibility<LangOpts<"TypeVisibilityMode">, fvisibility.KeyPath>;
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -3739,28 +3739,7 @@
     Opts.GNUCVersion = Major * 100 * 100 + Minor * 100 + Patch;
   }
 
-  // In AIX OS, the -mignore-xcoff-visibility is enable by default if there is
-  // no -fvisibility=* option.
-  // This is the reason why '-fvisibility' needs to be always generated:
-  // its absence implies '-mignore-xcoff-visibility'.
-  //
-  // Suppose the original cc1 command line does contain '-fvisibility default':
-  // '-mignore-xcoff-visibility' should not be implied.
-  // * If '-fvisibility' is not generated (as most options with default values
-  //   don't), its absence would imply '-mignore-xcoff-visibility'. This changes
-  //   the command line semantics.
-  // * If '-fvisibility' is generated regardless of its presence and value,
-  //   '-mignore-xcoff-visibility' won't be implied and the command line
-  //   semantics are kept intact.
-  //
-  // When the original cc1 command line does **not** contain '-fvisibility',
-  // '-mignore-xcoff-visibility' is implied. The generated command line will
-  // contain both '-fvisibility default' and '-mignore-xcoff-visibility' and
-  // subsequent calls to `CreateFromArgs`/`generateCC1CommandLine` will always
-  // produce the same arguments.
-
-  if (T.isOSAIX() && (Args.hasArg(OPT_mignore_xcoff_visibility) ||
-                      !Args.hasArg(OPT_fvisibility)))
+  if (T.isOSAIX() && (Args.hasArg(OPT_mignore_xcoff_visibility)))
     Opts.IgnoreXCOFFVisibility = 1;
 
   if (Args.hasArg(OPT_ftrapv)) {
diff --git a/clang/test/CodeGen/PowerPC/aix-ignore-xcoff-visibility.cpp b/clang/test/CodeGen/PowerPC/aix-ignore-xcoff-visibility.cpp
--- a/clang/test/CodeGen/PowerPC/aix-ignore-xcoff-visibility.cpp
+++ b/clang/test/CodeGen/PowerPC/aix-ignore-xcoff-visibility.cpp
@@ -1,8 +1,8 @@
 // RUN: %clang_cc1 -no-opaque-pointers -triple powerpc-unknown-aix -emit-llvm -o - -x c++ %s  | \
-// RUN: FileCheck -check-prefix=NOVISIBILITY-IR %s
+// RUN: FileCheck -check-prefix=VISIBILITY-IR %s
 
 // RUN: %clang_cc1 -no-opaque-pointers -triple powerpc-unknown-aix -emit-llvm -round-trip-args -o - -x c++ %s  | \
-// RUN: FileCheck -check-prefix=NOVISIBILITY-IR %s
+// RUN: FileCheck -check-prefix=VISIBILITY-IR %s
 
 // RUN: %clang_cc1 -no-opaque-pointers -triple powerpc-unknown-aix -mignore-xcoff-visibility -fvisibility default -emit-llvm -o - -x c++ %s  | \
 // RUN: FileCheck -check-prefix=NOVISIBILITY-IR %s
diff --git a/clang/test/CodeGen/PowerPC/aix-visibility-inlines-hidden.cpp b/clang/test/CodeGen/PowerPC/aix-visibility-inlines-hidden.cpp
--- a/clang/test/CodeGen/PowerPC/aix-visibility-inlines-hidden.cpp
+++ b/clang/test/CodeGen/PowerPC/aix-visibility-inlines-hidden.cpp
@@ -1,13 +1,13 @@
 // RUN: %clang_cc1 -triple powerpc-unknown-aix -mcmodel=large -emit-llvm -o - -x c++ %s  | \
-// RUN: FileCheck -check-prefix=NOVISIBILITY-IR %s
+// RUN: FileCheck -check-prefix=VISIBILITY-IR %s
 
 // RUN: %clang_cc1 -triple powerpc-unknown-aix -mcmodel=large \
 // RUN:            -fvisibility-inlines-hidden -emit-llvm -o - -x c++ %s  | \
-// RUN: FileCheck -check-prefix=NOVISIBILITY-IR %s
+// RUN: FileCheck -check-prefixes=VISIBILITY-IR,HIDDENINLINE-IR %s
 
 // RUN: %clang_cc1 -triple powerpc-unknown-aix -mcmodel=large -fvisibility-inlines-hidden \
 // RUN:            -fvisibility default -emit-llvm -o - -x c++ %s  | \
-// RUN: FileCheck -check-prefix=VISIBILITY-IR %s
+// RUN: FileCheck -check-prefixes=VISIBILITY-IR,HIDDENINLINE-IR %s
 
 // RUN: %clang_cc1 -triple powerpc-unknown-aix -mcmodel=large -mignore-xcoff-visibility -emit-llvm \
 // RUN:            -fvisibility-inlines-hidden -fvisibility default -o - -x c++ %s  | \
@@ -30,7 +30,7 @@
   return x;
 }
 
-// VISIBILITY-IR:     define linkonce_odr hidden void @_Z1fv()
+// HIDDENINLINE-IR:     define linkonce_odr hidden void @_Z1fv()
 // NOVISIBILITY-IR:   define linkonce_odr void @_Z1fv()
 
 // VISIBILITY-IR:     define linkonce_odr hidden void @_Z3foov()