diff options
| -rw-r--r-- | include/clang/Basic/DiagnosticSemaKinds.td | 9 | ||||
| -rw-r--r-- | lib/Sema/SemaExpr.cpp | 32 | ||||
| -rw-r--r-- | test/Sema/inline.c | 20 |
3 files changed, 61 insertions, 0 deletions
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td index e98c9f613b..eff5bab77d 100644 --- a/include/clang/Basic/DiagnosticSemaKinds.td +++ b/include/clang/Basic/DiagnosticSemaKinds.td @@ -2998,6 +2998,15 @@ def warn_undefined_internal : Warning< DiagGroup<"undefined-internal">; def note_used_here : Note<"used here">; +def warn_internal_in_extern_inline : ExtWarn< + "%select{function|variable}0 %1 has internal linkage but is used in an " + "inline %select{function|method}2 with external linkage">, + InGroup<DiagGroup<"internal-linkage-in-inline"> >; +def note_internal_decl_declared_here : Note< + "%0 declared here">; +def note_convert_inline_to_static : Note< + "use 'static' to give inline function %0 internal linkage">; + def warn_redefinition_of_typedef : ExtWarn< "redefinition of typedef %0 is a C11 feature">, InGroup<DiagGroup<"typedef-redefinition"> >; diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp index bc0188f10b..9c6efd3c10 100644 --- a/lib/Sema/SemaExpr.cpp +++ b/lib/Sema/SemaExpr.cpp @@ -182,6 +182,38 @@ bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc, // Warn if this is used but marked unused. if (D->hasAttr<UnusedAttr>()) Diag(Loc, diag::warn_used_but_marked_unused) << D->getDeclName(); + + // Warn if we're in an extern inline function referring to a decl + // with internal linkage. (C99 6.7.4p3) + // FIXME: This is not explicitly forbidden in C++, but it's not clear + // what the correct behavior is. We should probably still have a warning. + // (However, in C++ const variables have internal linkage by default, while + // functions still have external linkage by default, so this warning becomes + // very noisy.) + if (!getLangOpts().CPlusPlus) { + if (FunctionDecl *Current = getCurFunctionDecl()) { + if (Current->isInlined() && Current->getLinkage() > InternalLinkage) { + if (D->getLinkage() == InternalLinkage) { + Diag(Loc, diag::warn_internal_in_extern_inline) + << !isa<FunctionDecl>(D) << D << isa<CXXMethodDecl>(Current); + + // If the user didn't explicitly specify a storage class, + // suggest adding "static" to fix the problem. + const FunctionDecl *FirstDecl = Current->getCanonicalDecl(); + if (FirstDecl->getStorageClassAsWritten() == SC_None) { + SourceLocation DeclBegin = FirstDecl->getSourceRange().getBegin(); + Diag(DeclBegin, diag::note_convert_inline_to_static) + << Current << FixItHint::CreateInsertion(DeclBegin, "static "); + } + + Diag(D->getCanonicalDecl()->getLocation(), + diag::note_internal_decl_declared_here) + << D; + } + } + } + } + return false; } diff --git a/test/Sema/inline.c b/test/Sema/inline.c index 3c99f24337..37dba8c382 100644 --- a/test/Sema/inline.c +++ b/test/Sema/inline.c @@ -4,3 +4,23 @@ inline int a; // expected-error{{'inline' can only appear on functions}} typedef inline int b; // expected-error{{'inline' can only appear on functions}} int d(inline int a); // expected-error{{'inline' can only appear on functions}} + + +// Check the use of static variables in non-static inline functions. +static int staticVar; // expected-note 2 {{'staticVar' declared here}} +static int staticFunction(); // expected-note 2 {{'staticFunction' declared here}} + +inline int useStatic () { // expected-note 2 {{use 'static' to give inline function 'useStatic' internal linkage}} + staticFunction(); // expected-warning{{function 'staticFunction' has internal linkage but is used in an inline function with external linkage}} + return staticVar; // expected-warning{{variable 'staticVar' has internal linkage but is used in an inline function with external linkage}} +} + +extern inline int useStaticFromExtern () { // no suggestions + staticFunction(); // expected-warning{{function 'staticFunction' has internal linkage but is used in an inline function with external linkage}} + return staticVar; // expected-warning{{variable 'staticVar' has internal linkage but is used in an inline function with external linkage}} +} + +static inline int useStaticFromStatic () { + staticFunction(); // no-warning + return staticVar; // no-warning +} |