From 48f80aa9abf55d5a2e195e2e8a58fb6e12f3887c Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Wed, 9 Jul 2014 17:15:52 +0000
Subject: [PATCH] Sema: Allow aliases to have incomplete type
gcc supports this behavior and it is pervasively used inside the Linux
kernel.
Note that both gcc and clang will reject code that attempts to do this
in a C++ language mode.
This fixes PR17998.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@212631 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/Sema/SemaDecl.cpp | 12 +++++++-----
test/Sema/attr-alias-elf.c | 3 +++
2 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 82d28fa0827..13a77f15eb2 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -8897,11 +8897,13 @@ void Sema::ActOnUninitializedDecl(Decl *RealDecl,
if (Var->isInvalidDecl())
return;
- if (RequireCompleteType(Var->getLocation(),
- Context.getBaseElementType(Type),
- diag::err_typecheck_decl_incomplete_type)) {
- Var->setInvalidDecl();
- return;
+ if (!Var->hasAttr<AliasAttr>()) {
+ if (RequireCompleteType(Var->getLocation(),
+ Context.getBaseElementType(Type),
+ diag::err_typecheck_decl_incomplete_type)) {
+ Var->setInvalidDecl();
+ return;
+ }
}
// The variable can not have an abstract class type.
diff --git a/test/Sema/attr-alias-elf.c b/test/Sema/attr-alias-elf.c
index 04d13924ac1..f14514dccd2 100644
--- a/test/Sema/attr-alias-elf.c
+++ b/test/Sema/attr-alias-elf.c
@@ -64,3 +64,6 @@ void test3_foo() __attribute__((alias("test3_bar")));
__attribute__((section("test"))) void test4_bar() { }
void test4_foo() __attribute__((section("test")));
void test4_foo() __attribute__((alias("test4_bar")));
+
+int test5_bar = 0;
+extern struct incomplete_type test5_foo __attribute__((alias("test5_bar")));
--
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