c++: Don't upgrade TLS model if TLS model isn't set.

Don't upgrade TLS model when cplus_decl_attributes is called on a thread
local variable whose TLS model isn't set yet.

gcc/cp/

	PR c++/121889
	* decl2.cc (cplus_decl_attributes): Don't upgrade TLS model if
	TLS model isn't set yet.

gcc/testsuite/

	PR c++/121889
	* g++.dg/tls/pr121889.C: New test.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>

diff --git a/gcc/cp/decl2.cc b/gcc/cp/decl2.cc
index c9cca7b0270b3ca12fc4b227a8fdd2d05652eaa8..4564fdc45e01202bfa0edbb4cd1a067f411627bf 100644 (file)
--- a/gcc/cp/decl2.cc
+++ b/gcc/cp/decl2.cc
@@ -2018,9 +2018,13 @@ cplus_decl_attributes (tree *decl, tree attributes, int flags)
     {
       // tls_model attribute can set a stronger TLS access model.
       tls_model model = DECL_TLS_MODEL (*decl);
-      tls_model default_model = decl_default_tls_model (*decl);
-      if (default_model > model)
-       set_decl_tls_model (*decl, default_model);
+      // Don't upgrade TLS model if TLS model isn't set yet.
+      if (model != TLS_MODEL_NONE)
+       {
+         tls_model default_model = decl_default_tls_model (*decl);
+         if (default_model > model)
+           set_decl_tls_model (*decl, default_model);
+       }
     }
 }
 \f

diff --git a/gcc/testsuite/g++.dg/tls/pr121889.C b/gcc/testsuite/g++.dg/tls/pr121889.C
new file mode 100644 (file)
index 0000000..881855a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/tls/pr121889.C
@@ -0,0 +1,9 @@
+// { dg-do compile { target c++11 } }
+// { dg-require-effective-target tls }
+// { dg-options "-O2" }
+// { dg-add-options tls }
+
+extern void pthread_key_create();
+static __typeof(pthread_key_create) __gthrw___pthread_key_create
+    __attribute__((__weakref__("")));
+template <class> void zeta_imp_odd_integer() { thread_local int digits; }