[clang-tidy] insert static keyword in correct position for misc-use-internal-linkage (#108792)

Fixes: #108760

---------

Co-authored-by: Danny Mösch <[email protected]>

Author: HerrCai0907

clang-tools-extra/clang-tidy/misc/UseInternalLinkageCheck.cpp

@@ -8,12 +8,15 @@
 
 #include "UseInternalLinkageCheck.h"
 #include "../utils/FileExtensionsUtils.h"
+#include "../utils/LexerUtils.h"
 #include "clang/AST/Decl.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
 #include "clang/ASTMatchers/ASTMatchers.h"
 #include "clang/ASTMatchers/ASTMatchersMacros.h"
 #include "clang/Basic/SourceLocation.h"
 #include "clang/Basic/Specifiers.h"
+#include "clang/Basic/TokenKinds.h"
+#include "clang/Lex/Token.h"
 #include "llvm/ADT/STLExtras.h"
 
 using namespace clang::ast_matchers;
@@ -113,7 +116,7 @@ static constexpr StringRef Message =
 void UseInternalLinkageCheck::check(const MatchFinder::MatchResult &Result) {
   if (const auto *FD = Result.Nodes.getNodeAs<FunctionDecl>("fn")) {
     DiagnosticBuilder DB = diag(FD->getLocation(), Message) << "function" << FD;
-    SourceLocation FixLoc = FD->getTypeSpecStartLoc();
+    const SourceLocation FixLoc = FD->getInnerLocStart();
     if (FixLoc.isInvalid() || FixLoc.isMacroID())
       return;
     if (FixMode == FixModeKind::UseStatic)
@@ -128,7 +131,7 @@ void UseInternalLinkageCheck::check(const MatchFinder::MatchResult &Result) {
       return;
 
     DiagnosticBuilder DB = diag(VD->getLocation(), Message) << "variable" << VD;
-    SourceLocation FixLoc = VD->getTypeSpecStartLoc();
+    const SourceLocation FixLoc = VD->getInnerLocStart();
     if (FixLoc.isInvalid() || FixLoc.isMacroID())
       return;
     if (FixMode == FixModeKind::UseStatic)

clang-tools-extra/clang-tidy/utils/LexerUtils.cpp

@@ -24,13 +24,15 @@ getPreviousTokenAndStart(SourceLocation Location, const SourceManager &SM,
   if (Location.isInvalid())
     return {Token, Location};
 
-  auto StartOfFile = SM.getLocForStartOfFile(SM.getFileID(Location));
+  const auto StartOfFile = SM.getLocForStartOfFile(SM.getFileID(Location));
   while (Location != StartOfFile) {
     Location = Lexer::GetBeginningOfToken(Location, SM, LangOpts);
     if (!Lexer::getRawToken(Location, Token, SM, LangOpts) &&
         (!SkipComments || !Token.is(tok::comment))) {
       break;
     }
+    if (Location == StartOfFile)
+      return {Token, Location};
     Location = Location.getLocWithOffset(-1);
   }
   return {Token, Location};

clang-tools-extra/docs/ReleaseNotes.rst

@@ -195,6 +195,10 @@ Changes in existing checks
   <clang-tidy/checks/modernize/loop-convert>` check to fix false positive when
   using loop variable in initializer of lambda capture.
 
+- Improved :doc:`misc-use-internal-linkage
+  <clang-tidy/checks/misc/use-internal-linkage>` check to insert ``static`` keyword
+  before type qualifiers such as ``const`` and ``volatile``.
+
 - Improved :doc:`modernize-min-max-use-initializer-list
   <clang-tidy/checks/modernize/min-max-use-initializer-list>` check by fixing
   a false positive when only an implicit conversion happened inside an

clang-tools-extra/test/clang-tidy/checkers/misc/use-internal-linkage-func.cpp

@@ -17,6 +17,41 @@ void func_cpp_inc();
 // CHECK-MESSAGES: :[[@LINE-1]]:6: warning: function 'func_cpp_inc'
 // CHECK-FIXES: static void func_cpp_inc();
 
+int* func_cpp_inc_return_ptr();
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: function 'func_cpp_inc_return_ptr'
+// CHECK-FIXES: static int* func_cpp_inc_return_ptr();
+
+const int* func_cpp_inc_return_const_ptr();
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: function 'func_cpp_inc_return_const_ptr'
+// CHECK-FIXES: static const int* func_cpp_inc_return_const_ptr();
+
+int const* func_cpp_inc_return_ptr_const();
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: function 'func_cpp_inc_return_ptr_const'
+// CHECK-FIXES: static int const* func_cpp_inc_return_ptr_const();
+
+int * const func_cpp_inc_return_const();
+// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: function 'func_cpp_inc_return_const'
+// CHECK-FIXES: static int * const func_cpp_inc_return_const();
+
+volatile const int* func_cpp_inc_return_volatile_const_ptr();
+// CHECK-MESSAGES: :[[@LINE-1]]:21: warning: function 'func_cpp_inc_return_volatile_const_ptr'
+// CHECK-FIXES: static volatile const int* func_cpp_inc_return_volatile_const_ptr();
+
+[[nodiscard]] void func_nodiscard();
+// CHECK-MESSAGES: :[[@LINE-1]]:20: warning: function 'func_nodiscard'
+// CHECK-FIXES: {{\[\[nodiscard\]\]}} static void func_nodiscard();
+
+#define NDS [[nodiscard]]
+#define NNDS
+
+NDS void func_nds();
+// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: function 'func_nds'
+// CHECK-FIXES: NDS static void func_nds();
+
+NNDS void func_nnds();
+// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: function 'func_nnds'
+// CHECK-FIXES: NNDS static void func_nnds();
+
 #include "func_cpp.inc"
 
 void func_h_inc();

clang-tools-extra/test/clang-tidy/checkers/misc/use-internal-linkage-var.cpp

@@ -13,6 +13,18 @@ T global_template;
 // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: variable 'global_template'
 // CHECK-FIXES: static T global_template;
 
+int const* ptr_const_star;
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: variable 'ptr_const_star'
+// CHECK-FIXES: static int const* ptr_const_star;
+
+const int* const_ptr_star;
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: variable 'const_ptr_star'
+// CHECK-FIXES: static const int* const_ptr_star;
+
+const volatile int* const_volatile_ptr_star;
+// CHECK-MESSAGES: :[[@LINE-1]]:21: warning: variable 'const_volatile_ptr_star'
+// CHECK-FIXES: static const volatile int* const_volatile_ptr_star;
+
 int gloabl_header;
 
 extern int global_extern;