diff --git a/clang/lib/Driver/ToolChains/Arch/ARM.h b/clang/lib/Driver/ToolChains/Arch/ARM.h
--- a/clang/lib/Driver/ToolChains/Arch/ARM.h
+++ b/clang/lib/Driver/ToolChains/Arch/ARM.h
@@ -55,7 +55,7 @@
                          llvm::Triple &triple);
 bool isHardTPSupported(const llvm::Triple &Triple);
 ReadTPMode getReadTPMode(const Driver &D, const llvm::opt::ArgList &Args,
-                         const llvm::Triple &Triple);
+                         const llvm::Triple &Triple, bool ForAS);
 void setArchNameInTriple(const Driver &D, const llvm::opt::ArgList &Args,
                          types::ID InputType, llvm::Triple &Triple);
 
diff --git a/clang/lib/Driver/ToolChains/Arch/ARM.cpp b/clang/lib/Driver/ToolChains/Arch/ARM.cpp
--- a/clang/lib/Driver/ToolChains/Arch/ARM.cpp
+++ b/clang/lib/Driver/ToolChains/Arch/ARM.cpp
@@ -159,14 +159,15 @@
 
 // Select mode for reading thread pointer (-mtp=soft/cp15).
 arm::ReadTPMode arm::getReadTPMode(const Driver &D, const ArgList &Args,
-                                   const llvm::Triple &Triple) {
+                                   const llvm::Triple &Triple, bool ForAS) {
   if (Arg *A = Args.getLastArg(options::OPT_mtp_mode_EQ)) {
     arm::ReadTPMode ThreadPointer =
         llvm::StringSwitch<arm::ReadTPMode>(A->getValue())
             .Case("cp15", ReadTPMode::Cp15)
             .Case("soft", ReadTPMode::Soft)
             .Default(ReadTPMode::Invalid);
-    if (ThreadPointer == ReadTPMode::Cp15 && !isHardTPSupported(Triple)) {
+    if (ThreadPointer == ReadTPMode::Cp15 && !isHardTPSupported(Triple) &&
+        !ForAS) {
       D.Diag(diag::err_target_unsupported_tp_hard) << Triple.getArchName();
       return ReadTPMode::Invalid;
     }
@@ -488,7 +489,7 @@
     }
   }
 
-  if (getReadTPMode(D, Args, Triple) == ReadTPMode::Cp15)
+  if (getReadTPMode(D, Args, Triple, ForAS) == ReadTPMode::Cp15)
     Features.push_back("+read-tp-hard");
 
   const Arg *ArchArg = Args.getLastArg(options::OPT_march_EQ);
diff --git a/clang/test/Driver/clang-translation.c b/clang/test/Driver/clang-translation.c
--- a/clang/test/Driver/clang-translation.c
+++ b/clang/test/Driver/clang-translation.c
@@ -126,6 +126,10 @@
 // RUN: FileCheck -check-prefix=ARM_THREAD_POINTER-HARD %s
 // ARM_THREAD_POINTER-HARD: "-target-feature" "+read-tp-hard"
 
+// RUN: %clang -target armv5t-linux -mtp=cp15 -x assembler -### %s 2>&1 | \
+// RUN: FileCheck -check-prefix=ARMv5_THREAD_POINTER_ASSEMBLER %s
+// ARMv5_THREAD_POINTER_ASSEMBLER-NOT: hardware TLS register is not supported for the armv5 sub-architecture
+
 // RUN: %clang -target armv6-linux -mthumb -mtp=cp15 -### -S %s 2>&1 | \
 // RUN: FileCheck -check-prefix=THUMBv6_THREAD_POINTER_UNSUPP %s
 // RUN: %clang -target thumbv6-linux -mthumb -mtp=cp15 -### -S %s 2>&1 | \