From: Abramo Bagnara <abramo.bagnara@gmail.com>
Date: Tue, 11 Jan 2011 15:16:52 +0000 (+0000)
Subject: Added warning about invalid register specification for local variables.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=2b57aefea762f526405937b3c01901f8e1047edb;p=clang

Added warning about invalid register specification for local variables.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@123236 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 5b5bf84b7b..8c3a57622b 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -3029,6 +3029,8 @@ let CategoryName = "Inline Assembly Issue" in {
   def err_asm_tying_incompatible_types : Error<
     "unsupported inline asm: input with type %0 matching output with type %1">;
   def err_asm_unknown_register_name : Error<"unknown register name '%0' in asm">;
+  def warn_asm_label_on_auto_decl : Warning<
+    "ignored asm label '%0' on automatic variable">;
   def err_invalid_asm_cast_lvalue : Error<
     "invalid use of a cast in a inline asm context requiring an l-value: "
     "remove the cast or build with -fheinous-gnu-extensions">;
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 28ae8d23c7..4d67ff22ac 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -2997,10 +2997,24 @@ Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC,
     // The parser guarantees this is a string.
     StringLiteral *SE = cast<StringLiteral>(E);
     llvm::StringRef Label = SE->getString();
-    if (S->getFnParent() != 0 &&
-        !Context.Target.isValidGCCRegisterName(Label))
-      Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
-    NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 
+    if (S->getFnParent() != 0) {
+      switch (SC) {
+      case SC_None:
+      case SC_Auto:
+        Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label;
+        break;
+      case SC_Register:
+        if (!Context.Target.isValidGCCRegisterName(Label))
+          Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
+        break;
+      case SC_Static:
+      case SC_Extern:
+      case SC_PrivateExtern:
+        break;
+      }
+    }
+
+    NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0),
                                                 Context, Label));
   }
 
diff --git a/test/Sema/asm.c b/test/Sema/asm.c
index af6754a68b..7f0f396b9d 100644
--- a/test/Sema/asm.c
+++ b/test/Sema/asm.c
@@ -92,6 +92,16 @@ void test9(int i) {
   asm("" : [foo] "=r" (i), "=r"(i) : "[foo]1"(i)); // expected-error{{invalid input constraint '[foo]1' in asm}}
 }
 
+register int g asm("dx"); // expected-error{{global register variables are not supported}}
+
 void test10(void){
-        register unsigned long long bar asm("foo"); // expected-error {{unknown register name 'foo' in asm}}
+  static int g asm ("g_asm") = 0;
+  extern int gg asm ("gg_asm");
+  __private_extern__ int ggg asm ("ggg_asm");
+
+  int a asm ("a_asm"); // expected-warning{{ignored asm label 'a_asm' on automatic variable}}
+  auto int aa asm ("aa_asm"); // expected-warning{{ignored asm label 'aa_asm' on automatic variable}}
+
+  register int r asm ("cx");
+  register int rr asm ("rr_asm"); // expected-error{{unknown register name 'rr_asm' in asm}}
 }