Complain about attempts to use 'protected' visibility on targets
like Darwin that don't support it. We should also complain about
invalid -fvisibility=protected, but that information doesn't seem
to exist at the most appropriate time, so I've left a FIXME behind.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@149186 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 948236e..7888ce5 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1740,6 +1740,9 @@
def warn_attribute_type_not_supported : Warning<
"'%0' attribute argument not supported: %1">;
def warn_attribute_unknown_visibility : Warning<"unknown visibility '%0'">;
+def warn_attribute_protected_visibility :
+ Warning<"target does not support 'protected' visibility; using 'default'">,
+ InGroup<DiagGroup<"unsupported-visibility">>;
def err_unknown_machine_mode : Error<"unknown machine mode %0">;
def err_unsupported_machine_mode : Error<"unsupported machine mode %0">;
def err_mode_not_primitive : Error<
diff --git a/include/clang/Basic/TargetInfo.h b/include/clang/Basic/TargetInfo.h
index b1e1cbd..966797c 100644
--- a/include/clang/Basic/TargetInfo.h
+++ b/include/clang/Basic/TargetInfo.h
@@ -479,6 +479,19 @@
const unsigned RegNum;
};
+ /// hasProtectedVisibility - Does this target support "protected"
+ /// visibility?
+ ///
+ /// Any target which dynamic libraries will naturally support
+ /// something like "default" (meaning that the symbol is visible
+ /// outside this shared object) and "hidden" (meaning that it isn't)
+ /// visibilities, but "protected" is really an ELF-specific concept
+ /// with wierd semantics designed around the convenience of dynamic
+ /// linker implementations. Which is not to suggest that there's
+ /// consistent target-independent semantics for "default" visibility
+ /// either; the entire thing is pretty badly mangled.
+ virtual bool hasProtectedVisibility() const { return true; }
+
virtual bool useGlobalsForAutomaticVariables() const { return false; }
/// getCFStringSection - Return the section to use for CFString
diff --git a/lib/Basic/Targets.cpp b/lib/Basic/Targets.cpp
index 5cdb36f..5dc63e7 100644
--- a/lib/Basic/Targets.cpp
+++ b/lib/Basic/Targets.cpp
@@ -218,6 +218,12 @@
return "__TEXT,__StaticInit,regular,pure_instructions";
}
+ /// Darwin does not support protected visibility. Darwin's "default"
+ /// is very similar to ELF's "protected"; Darwin requires a "weak"
+ /// attribute on declarations that can be dynamically replaced.
+ virtual bool hasProtectedVisibility() const {
+ return false;
+ }
};
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index a189155..e9bb303 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -1792,6 +1792,7 @@
else if (Vis == "hidden")
Opts.setVisibilityMode(HiddenVisibility);
else if (Vis == "protected")
+ // FIXME: diagnose if target does not support protected visibility
Opts.setVisibilityMode(ProtectedVisibility);
else
Diags.Report(diag::err_drv_invalid_value)
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index aa827a4..d4b9988 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -1694,9 +1694,16 @@
type = VisibilityAttr::Hidden;
else if (TypeStr == "internal")
type = VisibilityAttr::Hidden; // FIXME
- else if (TypeStr == "protected")
- type = VisibilityAttr::Protected;
- else {
+ else if (TypeStr == "protected") {
+ // Complain about attempts to use protected visibility on targets
+ // (like Darwin) that don't support it.
+ if (!S.Context.getTargetInfo().hasProtectedVisibility()) {
+ S.Diag(Attr.getLoc(), diag::warn_attribute_protected_visibility);
+ type = VisibilityAttr::Default;
+ } else {
+ type = VisibilityAttr::Protected;
+ }
+ } else {
S.Diag(Attr.getLoc(), diag::warn_attribute_unknown_visibility) << TypeStr;
return;
}
diff --git a/test/CodeGenCXX/thunks.cpp b/test/CodeGenCXX/thunks.cpp
index 7c80b96..04d0820 100644
--- a/test/CodeGenCXX/thunks.cpp
+++ b/test/CodeGenCXX/thunks.cpp
@@ -1,5 +1,5 @@
-// RUN: %clang_cc1 %s -triple=x86_64-apple-darwin10 -emit-llvm -o - | FileCheck %s
-// RUN: %clang_cc1 %s -triple=x86_64-apple-darwin10 -fhidden-weak-vtables -emit-llvm -o - | FileCheck -check-prefix=HIDDEN %s
+// RUN: %clang_cc1 %s -triple=x86_64-pc-linux-gnu -emit-llvm -o - | FileCheck %s
+// RUN: %clang_cc1 %s -triple=x86_64-pc-linux-gnu -fhidden-weak-vtables -emit-llvm -o - | FileCheck -check-prefix=HIDDEN %s
namespace Test1 {
diff --git a/test/Sema/attr-visibility.c b/test/Sema/attr-visibility.c
new file mode 100644
index 0000000..5cf2695
--- /dev/null
+++ b/test/Sema/attr-visibility.c
@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fsyntax-only -verify %s
+
+void test0() __attribute__((visibility("default")));
+void test1() __attribute__((visibility("hidden")));
+void test2() __attribute__((visibility("internal")));
+
+// rdar://problem/10753392
+void test3() __attribute__((visibility("protected"))); // expected-warning {{target does not support 'protected' visibility; using 'default'}}
+