1 //===--- Linkage.h - Linkage enumeration and utilities ----------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// \brief Defines the Linkage enumeration and various utility functions.
13 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CLANG_BASIC_LINKAGE_H
15 #define LLVM_CLANG_BASIC_LINKAGE_H
19 /// \brief Describes the different kinds of linkage
20 /// (C++ [basic.link], C99 6.2.2) that an entity may have.
22 /// \brief No linkage, which means that the entity is unique and
23 /// can only be referred to from within its scope.
26 /// \brief Internal linkage, which indicates that the entity can
27 /// be referred to from within the translation unit (but not other
28 /// translation units).
31 /// \brief External linkage within a unique namespace.
33 /// From the language perspective, these entities have external
34 /// linkage. However, since they reside in an anonymous namespace,
35 /// their names are unique to this translation unit, which is
36 /// equivalent to having internal linkage from the code-generation
38 UniqueExternalLinkage,
40 /// \brief External linkage, which indicates that the entity can
41 /// be referred to from other translation units.
45 /// \brief Describes the different kinds of language linkage
46 /// (C++ [dcl.link]) that an entity may have.
47 enum LanguageLinkage {
53 /// \brief A more specific kind of linkage than enum Linkage.
55 /// This is relevant to CodeGen and AST file reading.
61 GVA_TemplateInstantiation,
62 GVA_ExplicitTemplateInstantiation
65 /// \brief Determine whether the given linkage is semantically external.
66 inline bool isExternalLinkage(Linkage L) {
67 return L == UniqueExternalLinkage || L == ExternalLinkage;
70 /// \brief Compute the minimum linkage given two linages.
71 inline Linkage minLinkage(Linkage L1, Linkage L2) {
72 return L1 < L2? L1 : L2;
75 } // end namespace clang
77 #endif // LLVM_CLANG_BASIC_LINKAGE_H