PR middle-end/81824 - Warn for missing attributes with function aliases

gcc/c-family/ChangeLog:

	* c-attribs.c (handle_copy_attribute): Exclude inlining attributes.
	(handle_tls_model_attribute): Improve diagnostics.

gcc/testsuite/ChangeLog:

	* gcc.dg/attr-copy-5.c: New test.
	* gcc.dg/tls/diag-6.c: Adjust expected diagnostics.

From-SVN: r266084

5 files changed, 92 insertions, 9 deletions

diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index 165f9b7..26a2b4e 100644
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,9 @@
+2018-11-13  Martin Sebor  <msebor@redhat.com>
+
+	PR middle-end/81824
+	* c-attribs.c (handle_copy_attribute): Exclude inlining attributes.
+	(handle_tls_model_attribute): Improve diagnostics.
+
 2018-11-12  Jason Merrill  <jason@redhat.com>
 
 	* c-cppbuiltin.c (c_cpp_builtins): Define
diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
index 5e3b127..1657df7 100644
--- a/gcc/c-family/c-attribs.c
+++ b/gcc/c-family/c-attribs.c
@@ -2239,14 +2239,17 @@ handle_copy_attribute (tree *node, tree name, tree args,
       /* Copy decl attributes from REF to DECL.  */
       for (tree at = attrs; at; at = TREE_CHAIN (at))
 	{
-	  /* Avoid copying attributes that affect a symbol linkage or
-	     visibility since those in all likelihood only apply to
-	     the target.
+	  /* Avoid copying attributes that affect a symbol linkage,
+	     inlining, or visibility since those in all likelihood
+	     only apply to the target.
 	     FIXME: make it possible to specify which attributes to
 	     copy or not to copy in the copy attribute itself.  */
 	  tree atname = get_attribute_name (at);
 	  if (is_attribute_p ("alias", atname)
+	      || is_attribute_p ("always_inline", atname)
+	      || is_attribute_p ("gnu_inline", atname)
 	      || is_attribute_p ("ifunc", atname)
+	      || is_attribute_p ("noinline", atname)
 	      || is_attribute_p ("visibility", atname)
 	      || is_attribute_p ("weak", atname)
 	      || is_attribute_p ("weakref", atname))
@@ -2458,9 +2461,18 @@ handle_tls_model_attribute (tree *node, tree name, tree args,
   tree decl = *node;
   enum tls_model kind;
 
-  if (!VAR_P (decl) || !DECL_THREAD_LOCAL_P (decl))
+  if (!VAR_P (decl))
     {
-      warning (OPT_Wattributes, "%qE attribute ignored", name);
+      warning (OPT_Wattributes, "%qE attribute ignored because %qD "
+	       "is not a variable",
+	       name, decl);
+      return NULL_TREE;
+    }
+
+  if (!DECL_THREAD_LOCAL_P (decl))
+    {
+      warning (OPT_Wattributes, "%qE attribute ignored because %qD does "
+	       "not have thread storage duration", name, decl);
       return NULL_TREE;
     }
 
@@ -2468,7 +2480,7 @@ handle_tls_model_attribute (tree *node, tree name, tree args,
   id = TREE_VALUE (args);
   if (TREE_CODE (id) != STRING_CST)
     {
-      error ("tls_model argument not a string");
+      error ("%qE argument not a string", name);
       return NULL_TREE;
     }
 
@@ -2481,7 +2493,9 @@ handle_tls_model_attribute (tree *node, tree name, tree args,
   else if (!strcmp (TREE_STRING_POINTER (id), "global-dynamic"))
     kind = TLS_MODEL_GLOBAL_DYNAMIC;
   else
-    error ("tls_model argument must be one of \"local-exec\", \"initial-exec\", \"local-dynamic\" or \"global-dynamic\"");
+    error ("%qE argument must be one of %qs, %qs, %qs, or %qs",
+	   name,
+	   "local-exec", "initial-exec", "local-dynamic", "global-dynamic");
 
   set_decl_tls_model (decl, kind);
   return NULL_TREE;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f9a2ee4..919c478 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2018-11-13  Martin Sebor  <msebor@redhat.com>
+
+	PR middle-end/81824
+	* gcc.dg/attr-copy-5.c: New test.
+	* gcc.dg/tls/diag-6.c: Adjust expected diagnostics.
+
 2018-11-13  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/86991
diff --git a/gcc/testsuite/gcc.dg/attr-copy-5.c b/gcc/testsuite/gcc.dg/attr-copy-5.c
new file mode 100644
index 0000000..b085cf96
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/attr-copy-5.c
@@ -0,0 +1,57 @@
+/* PR middle-end/81824 - Warn for missing attributes with function aliases
+   Verify that attributes always_inline, gnu_inline, and noinline aren't
+   copied.  Also verify that copying attribute tls_model to a non-thread
+   variable triggers a warning.
+   { dg-do compile }
+   { dg-options "-Wall" }
+   { dg-require-effective-target tls } */
+
+#define ATTR(...)   __attribute__ ((__VA_ARGS__))
+
+ATTR (always_inline, gnu_inline, noreturn) inline int
+finline_noret (void)
+{
+  __builtin_abort ();
+  /* Expect no -Wreturn-type.  */
+}
+
+int call_finline_noret (void)
+{
+  finline_noret ();
+  /* Expect no -Wreturn-type.  */
+}
+
+
+ATTR (copy (finline_noret)) int
+fnoret (void);
+
+int call_fnoret (void)
+{
+  fnoret ();
+  /* Expect no -Wreturn-type.  */
+}
+
+
+/* Verify that attribute always_inline on an alias target doesn't
+   get copied and interfere with attribute noinline on the alias
+   (trigger a warning due to a conflict).  */
+
+ATTR (always_inline) static inline int
+finline (void) { return 0; }
+
+ATTR (alias ("finline"), noinline) int
+fnoinline (void);
+
+ATTR (copy (finline)) int
+fnoinline (void);
+
+
+ATTR (tls_model ("global-dynamic")) __thread int
+  tls_target;
+
+ATTR (alias ("tls_target"), copy (tls_target)) extern __thread int
+  thread_alias;
+
+
+ATTR (alias ("tls_target"), copy (tls_target)) extern int
+  alias;            /* { dg-warning ".tls_model. attribute ignored because .alias. does not have thread storage duration" } */
diff --git a/gcc/testsuite/gcc.dg/tls/diag-6.c b/gcc/testsuite/gcc.dg/tls/diag-6.c
index 71b0b95..171bf21 100644
--- a/gcc/testsuite/gcc.dg/tls/diag-6.c
+++ b/gcc/testsuite/gcc.dg/tls/diag-6.c
@@ -4,5 +4,5 @@
 int v __attribute__((tls_model("initial-exec"))); /* { dg-warning "attribute ignored" } */
 typedef int X __attribute__((tls_model("initial-exec"))); /* { dg-warning "attribute ignored" } */
 void f(int x __attribute__((tls_model("initial-exec")))); /* { dg-warning "attribute ignored" } */
-__thread int a __attribute__((tls_model(1))); /* { dg-error "tls_model argument not a string" } */
-__thread int b __attribute__((tls_model("unknown"))); /* { dg-error "tls_model argument must be one of" } */
+__thread int a __attribute__((tls_model(1))); /* { dg-error ".tls_model. argument not a string" } */
+__thread int b __attribute__((tls_model("unknown"))); /* { dg-error ".tls_model. argument must be one of" } */