[clang] Revert "[clang] Catch missing format attributes" (PR #98617)

via cfe-commits cfe-commits at lists.llvm.org
Fri Jul 12 03:59:08 PDT 2024


llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: Aaron Ballman (AaronBallman)

<details>
<summary>Changes</summary>

Reverts llvm/llvm-project#<!-- -->70024

It broke several post-commit bots:
https://lab.llvm.org/buildbot/#/builders/193/builds/896
https://lab.llvm.org/buildbot/#/builders/23/builds/925
https://lab.llvm.org/buildbot/#/builders/13/builds/686
and others

---

Patch is 41.74 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/98617.diff


9 Files Affected:

- (modified) clang/docs/ReleaseNotes.rst (-3) 
- (modified) clang/include/clang/Basic/DiagnosticGroups.td (+1) 
- (modified) clang/include/clang/Basic/DiagnosticSemaKinds.td (-3) 
- (modified) clang/include/clang/Sema/Attr.h (-7) 
- (modified) clang/include/clang/Sema/Sema.h (-4) 
- (modified) clang/lib/Sema/SemaDecl.cpp (-2) 
- (modified) clang/lib/Sema/SemaDeclAttr.cpp (+2-217) 
- (removed) clang/test/Sema/attr-format-missing.c (-403) 
- (removed) clang/test/Sema/attr-format-missing.cpp (-174) 


``````````diff
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index afcd3c655f0f6..781fc8ab1de1e 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -716,9 +716,6 @@ Improvements to Clang's diagnostics
 
 - Clang now diagnoses integer constant expressions that are folded to a constant value as an extension in more circumstances. Fixes #GH59863
 
-- Clang now diagnoses missing format attributes for non-template functions and
-  class/struct/union members. Fixes #GH60718
-
 Improvements to Clang's time-trace
 ----------------------------------
 
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index da6a3b2fe3571..2241f8481484e 100644
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -525,6 +525,7 @@ def MainReturnType : DiagGroup<"main-return-type">;
 def MaxUnsignedZero : DiagGroup<"max-unsigned-zero">;
 def MissingBraces : DiagGroup<"missing-braces">;
 def MissingDeclarations: DiagGroup<"missing-declarations">;
+def : DiagGroup<"missing-format-attribute">;
 def MissingIncludeDirs : DiagGroup<"missing-include-dirs">;
 def MissingNoreturn : DiagGroup<"missing-noreturn">;
 def MultiChar : DiagGroup<"multichar">;
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index f5c18edb65217..0ea3677355169 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1031,9 +1031,6 @@ def err_opencl_invalid_param : Error<
 def err_opencl_invalid_return : Error<
   "declaring function return value of type %0 is not allowed %select{; did you forget * ?|}1">;
 def warn_enum_value_overflow : Warning<"overflow in enumeration value">;
-def warn_missing_format_attribute : Warning<
-  "diagnostic behavior may be improved by adding the %0 format attribute to the declaration of %1">,
-  InGroup<DiagGroup<"missing-format-attribute">>, DefaultIgnore;
 def warn_pragma_options_align_reset_failed : Warning<
   "#pragma options align=reset failed: %0">,
   InGroup<IgnoredPragmas>;
diff --git a/clang/include/clang/Sema/Attr.h b/clang/include/clang/Sema/Attr.h
index 37c124ca7b454..3f0b10212789a 100644
--- a/clang/include/clang/Sema/Attr.h
+++ b/clang/include/clang/Sema/Attr.h
@@ -123,13 +123,6 @@ inline bool isInstanceMethod(const Decl *D) {
   return false;
 }
 
-inline bool checkIfMethodHasImplicitObjectParameter(const Decl *D) {
-  if (const auto *MethodDecl = dyn_cast<CXXMethodDecl>(D))
-    return MethodDecl->isInstance() &&
-           !MethodDecl->hasCXXExplicitFunctionObjectParameter();
-  return false;
-}
-
 /// Diagnose mutually exclusive attributes when present on a given
 /// declaration. Returns true if diagnosed.
 template <typename AttrTy>
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index e30252749d2c3..6be6f6725e5b7 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -4594,10 +4594,6 @@ class Sema final : public SemaBase {
 
   enum class RetainOwnershipKind { NS, CF, OS };
 
-  void DiagnoseMissingFormatAttributes(Stmt *Body, const FunctionDecl *FDecl);
-  std::vector<FormatAttr *>
-  GetMissingFormatAttributes(Stmt *Body, const FunctionDecl *FDecl);
-
   UuidAttr *mergeUuidAttr(Decl *D, const AttributeCommonInfo &CI,
                           StringRef UuidAsWritten, MSGuidDecl *GuidDecl);
 
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 0039df2a21bc6..80b5a8cd4bae6 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -15934,8 +15934,6 @@ Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
         }
       }
 
-      DiagnoseMissingFormatAttributes(Body, FD);
-
       // We might not have found a prototype because we didn't wish to warn on
       // the lack of a missing prototype. Try again without the checks for
       // whether we want to warn on the missing prototype.
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index 5166e61bb41d4..f2cd46d1e7c93 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -3508,7 +3508,7 @@ static void handleFormatAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
 
   // In C++ the implicit 'this' function parameter also counts, and they are
   // counted from one.
-  bool HasImplicitThisParam = checkIfMethodHasImplicitObjectParameter(D);
+  bool HasImplicitThisParam = isInstanceMethod(D);
   unsigned NumArgs = getFunctionOrMethodNumParams(D) + HasImplicitThisParam;
 
   IdentifierInfo *II = AL.getArgAsIdent(0)->Ident;
@@ -3621,7 +3621,7 @@ static void handleCallbackAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
     return;
   }
 
-  bool HasImplicitThisParam = checkIfMethodHasImplicitObjectParameter(D);
+  bool HasImplicitThisParam = isInstanceMethod(D);
   int32_t NumArgs = getFunctionOrMethodNumParams(D);
 
   FunctionDecl *FD = D->getAsFunction();
@@ -5320,221 +5320,6 @@ static void handlePreferredTypeAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   D->addAttr(::new (S.Context) PreferredTypeAttr(S.Context, AL, ParmTSI));
 }
 
-// This function is called only if function call is not inside template body.
-// TODO: Add call for function calls inside template body.
-// Emit warnings if parent function misses format attributes.
-void Sema::DiagnoseMissingFormatAttributes(Stmt *Body,
-                                           const FunctionDecl *FDecl) {
-  assert(FDecl);
-
-  // If there are no function body, exit.
-  if (!Body)
-    return;
-
-  // Get missing format attributes
-  std::vector<FormatAttr *> MissingFormatAttributes =
-      GetMissingFormatAttributes(Body, FDecl);
-  if (MissingFormatAttributes.empty())
-    return;
-
-  // Check if there are more than one format type found. In that case do not
-  // emit diagnostic.
-  const FormatAttr *FirstAttr = MissingFormatAttributes[0];
-  if (llvm::any_of(MissingFormatAttributes, [&](const FormatAttr *Attr) {
-        return FirstAttr->getType() != Attr->getType();
-      }))
-    return;
-
-  for (const FormatAttr *FA : MissingFormatAttributes) {
-    // If format index and first-to-check argument index are negative, it means
-    // that this attribute is only saved for multiple format types checking.
-    if (FA->getFormatIdx() < 0 || FA->getFirstArg() < 0)
-      continue;
-
-    // Emit diagnostic
-    SourceLocation Loc = FDecl->getLocation();
-    Diag(Loc, diag::warn_missing_format_attribute)
-        << FA->getType() << FDecl
-        << FixItHint::CreateInsertion(Loc,
-                                      (llvm::Twine("__attribute__((format(") +
-                                       FA->getType()->getName() + ", " +
-                                       llvm::Twine(FA->getFormatIdx()) + ", " +
-                                       llvm::Twine(FA->getFirstArg()) + ")))")
-                                          .str());
-  }
-}
-
-// Returns vector of format attributes. There are no two attributes with same
-// arguments in returning vector. There can be attributes that effectivelly only
-// store information about format type.
-std::vector<FormatAttr *>
-Sema::GetMissingFormatAttributes(Stmt *Body, const FunctionDecl *FDecl) {
-  unsigned int FunctionFormatArgumentIndexOffset =
-      checkIfMethodHasImplicitObjectParameter(FDecl) ? 2 : 1;
-
-  std::vector<FormatAttr *> MissingAttributes;
-
-  // Iterate over body statements.
-  for (auto *Child : Body->children()) {
-    // If child statement is compound statement, recursively get missing
-    // attributes.
-    if (dyn_cast_or_null<CompoundStmt>(Child)) {
-      std::vector<FormatAttr *> CompoundStmtMissingAttributes =
-          GetMissingFormatAttributes(Child, FDecl);
-
-      // If there are already missing attributes with same arguments, do not add
-      // duplicates.
-      for (FormatAttr *FA : CompoundStmtMissingAttributes) {
-        if (!llvm::any_of(MissingAttributes, [&](const FormatAttr *Attr) {
-              return FA->getType() == Attr->getType() &&
-                     FA->getFormatIdx() == Attr->getFormatIdx() &&
-                     FA->getFirstArg() == Attr->getFirstArg();
-            }))
-          MissingAttributes.push_back(FA);
-      }
-
-      continue;
-    }
-
-    ValueStmt *VS = dyn_cast_or_null<ValueStmt>(Child);
-    if (!VS)
-      continue;
-    Expr *TheExpr = VS->getExprStmt();
-    if (!TheExpr)
-      continue;
-    CallExpr *TheCall = dyn_cast_or_null<CallExpr>(TheExpr);
-    if (!TheCall)
-      continue;
-    const FunctionDecl *ChildFunction =
-        dyn_cast_or_null<FunctionDecl>(TheCall->getCalleeDecl());
-    if (!ChildFunction)
-      continue;
-
-    Expr **Args = TheCall->getArgs();
-    unsigned int NumArgs = TheCall->getNumArgs();
-
-    // If child expression is function, check if it is format function.
-    // If it is, check if parent function misses format attributes.
-
-    // If child function is format function and format arguments are not
-    // relevant to emit diagnostic, save only information about format type
-    // (format index and first-to-check argument index are set to -1).
-    // Information about format type is later used to determine if there are
-    // more than one format type found.
-
-    unsigned int ChildFunctionFormatArgumentIndexOffset =
-        checkIfMethodHasImplicitObjectParameter(ChildFunction) ? 2 : 1;
-
-    // Check if function has format attribute with forwarded format string.
-    IdentifierInfo *AttrType;
-    const ParmVarDecl *FormatArg;
-    if (!llvm::any_of(ChildFunction->specific_attrs<FormatAttr>(),
-                      [&](const FormatAttr *Attr) {
-                        AttrType = Attr->getType();
-
-                        int OffsetFormatIndex =
-                            Attr->getFormatIdx() -
-                            ChildFunctionFormatArgumentIndexOffset;
-                        if (OffsetFormatIndex < 0 ||
-                            (unsigned)OffsetFormatIndex >= NumArgs)
-                          return false;
-
-                        const auto *FormatArgExpr = dyn_cast<DeclRefExpr>(
-                            Args[OffsetFormatIndex]->IgnoreParenCasts());
-                        if (!FormatArgExpr)
-                          return false;
-
-                        FormatArg = dyn_cast_or_null<ParmVarDecl>(
-                            FormatArgExpr->getReferencedDeclOfCallee());
-                        if (!FormatArg)
-                          return false;
-
-                        return true;
-                      })) {
-      MissingAttributes.push_back(
-          FormatAttr::CreateImplicit(getASTContext(), AttrType, -1, -1));
-      continue;
-    }
-
-    // Do not add in a vector format attributes whose type is different than
-    // parent function attribute type.
-    if (llvm::any_of(FDecl->specific_attrs<FormatAttr>(),
-                     [&](const FormatAttr *FunctionAttr) {
-                       return AttrType != FunctionAttr->getType();
-                     }))
-      continue;
-
-    // Check if format string argument is parent function parameter.
-    unsigned int StringIndex = 0;
-    if (!llvm::any_of(FDecl->parameters(), [&](const ParmVarDecl *Param) {
-          if (Param != FormatArg)
-            return false;
-
-          StringIndex = Param->getFunctionScopeIndex() +
-                        FunctionFormatArgumentIndexOffset;
-
-          return true;
-        })) {
-      MissingAttributes.push_back(
-          FormatAttr::CreateImplicit(getASTContext(), AttrType, -1, -1));
-      continue;
-    }
-
-    unsigned NumOfParentFunctionParams = FDecl->getNumParams();
-
-    // Compare parent and calling function format attribute arguments (archetype
-    // and format string).
-    if (llvm::any_of(
-            FDecl->specific_attrs<FormatAttr>(), [&](const FormatAttr *Attr) {
-              if (Attr->getType() != AttrType)
-                return false;
-              int OffsetFormatIndex =
-                  Attr->getFormatIdx() - FunctionFormatArgumentIndexOffset;
-
-              if (OffsetFormatIndex < 0 ||
-                  (unsigned)OffsetFormatIndex >= NumOfParentFunctionParams)
-                return false;
-
-              if (FDecl->parameters()[OffsetFormatIndex] != FormatArg)
-                return false;
-
-              return true;
-            })) {
-      MissingAttributes.push_back(
-          FormatAttr::CreateImplicit(getASTContext(), AttrType, -1, -1));
-      continue;
-    }
-
-    // Get first argument index
-    unsigned FirstToCheck = [&]() -> unsigned {
-      if (!FDecl->isVariadic())
-        return 0;
-      const auto *FirstToCheckArg =
-          dyn_cast<DeclRefExpr>(Args[NumArgs - 1]->IgnoreParenCasts());
-      if (!FirstToCheckArg)
-        return 0;
-
-      if (FirstToCheckArg->getType().getCanonicalType() !=
-          Context.getBuiltinVaListType().getCanonicalType())
-        return 0;
-      return NumOfParentFunctionParams + FunctionFormatArgumentIndexOffset;
-    }();
-
-    // If there are already attributes which arguments matches arguments
-    // detected in this iteration, do not add new attribute as it would be
-    // duplicate.
-    if (!llvm::any_of(MissingAttributes, [&](const FormatAttr *Attr) {
-          return Attr->getType() == AttrType &&
-                 Attr->getFormatIdx() == StringIndex &&
-                 Attr->getFirstArg() == FirstToCheck;
-        }))
-      MissingAttributes.push_back(FormatAttr::CreateImplicit(
-          getASTContext(), AttrType, StringIndex, FirstToCheck));
-  }
-
-  return MissingAttributes;
-}
-
 //===----------------------------------------------------------------------===//
 // Microsoft specific attribute handlers.
 //===----------------------------------------------------------------------===//
diff --git a/clang/test/Sema/attr-format-missing.c b/clang/test/Sema/attr-format-missing.c
deleted file mode 100644
index 4f9e91eb1becb..0000000000000
--- a/clang/test/Sema/attr-format-missing.c
+++ /dev/null
@@ -1,403 +0,0 @@
-// RUN: %clang_cc1 -fsyntax-only -verify=expected,c_diagnostics -Wmissing-format-attribute %s
-// RUN: %clang_cc1 -fsyntax-only -Wmissing-format-attribute -fdiagnostics-parseable-fixits %s 2>&1 | FileCheck %s --check-prefixes=CHECK,C-CHECK
-// RUN: %clang_cc1 -fsyntax-only -x c++ -verify=expected,cpp_diagnostics -Wmissing-format-attribute %s
-// RUN: %clang_cc1 -fsyntax-only -x c++ -verify=expected,cpp_diagnostics -std=c++2b -Wmissing-format-attribute %s
-// RUN: %clang_cc1 -fsyntax-only -x c++ -verify=expected,cpp_diagnostics -std=c++23 -Wmissing-format-attribute %s
-// RUN: not %clang_cc1 -fsyntax-only -x c++ -Wmissing-format-attribute -fdiagnostics-parseable-fixits -triple x86_64-linux %s 2>&1 | FileCheck %s --check-prefixes=CHECK,CHECK-LIN64
-// RUN: not %clang_cc1 -fsyntax-only -x c++ -Wmissing-format-attribute -fdiagnostics-parseable-fixits -triple x86_64-windows %s 2>&1 | FileCheck %s --check-prefixes=CHECK
-// RUN: not %clang_cc1 -fsyntax-only -x c++ -Wmissing-format-attribute -fdiagnostics-parseable-fixits -triple i386-windows %s 2>&1 | FileCheck %s --check-prefixes=CHECK
-// RUN: not %clang_cc1 -fsyntax-only -x c++ -Wmissing-format-attribute -fdiagnostics-parseable-fixits -triple i386-windows %s 2>&1 | FileCheck %s --check-prefixes=CHECK
-
-#ifndef __cplusplus
-typedef unsigned short char16_t;
-typedef unsigned int char32_t;
-typedef __WCHAR_TYPE__ wchar_t;
-#endif
-
-typedef __SIZE_TYPE__ size_t;
-typedef __builtin_va_list va_list;
-
-__attribute__((__format__(__printf__, 1, 2)))
-int printf(const char *, ...); // #printf
-
-__attribute__((__format__(__scanf__, 1, 2)))
-int scanf(const char *, ...); // #scanf
-
-__attribute__((__format__(__printf__, 1, 0)))
-int vprintf(const char *, va_list); // #vprintf
-
-__attribute__((__format__(__scanf__, 1, 0)))
-int vscanf(const char *, va_list); // #vscanf
-
-__attribute__((__format__(__printf__, 2, 0)))
-int vsprintf(char *, const char *, va_list); // #vsprintf
-
-__attribute__((__format__(__printf__, 3, 0)))
-int vsnprintf(char *ch, size_t, const char *, va_list); // #vsnprintf
-
-__attribute__((__format__(__scanf__, 1, 4)))
-void f1(char *out, const size_t len, const char *format, ... /* args */) // #f1
-{
-    va_list args;
-    vsnprintf(out, len, format, args); // expected-no-warning@#f1
-}
-
-__attribute__((__format__(__printf__, 1, 4)))
-void f2(char *out, const size_t len, const char *format, ... /* args */) // #f2
-{
-    va_list args;
-    vsnprintf(out, len, format, args); // expected-warning@#f2 {{diagnostic behavior may be improved by adding the 'printf' format attribute to the declaration of 'f2'}}
-                                       // CHECK: fix-it:"{{.*}}":{[[@LINE-4]]:6-[[@LINE-4]]:6}:"__attribute__((format(printf, 3, 4)))"
-}
-
-void f3(char *out, va_list args) // #f3
-{
-    vprintf(out, args); // expected-warning@#f3 {{diagnostic behavior may be improved by adding the 'printf' format attribute to the declaration of 'f3'}}
-                        // CHECK: fix-it:"{{.*}}":{[[@LINE-3]]:6-[[@LINE-3]]:6}:"__attribute__((format(printf, 1, 0)))"
-}
-
-void f4(char* out, ... /* args */) // #f4
-{
-    va_list args;
-    vprintf("test", args); // expected-no-warning@#f4
-
-    const char *ch;
-    vprintf(ch, args); // expected-no-warning@#f4
-}
-
-void f5(va_list args) // #f5
-{
-    char *ch;
-    vscanf(ch, args); // expected-no-warning@#f5
-}
-
-void f6(char *out, va_list args) // #f6
-{
-    char *ch;
-    vprintf(ch, args); // expected-no-warning@#f6
-    vprintf("test", args); // expected-no-warning@#f6
-    vprintf(out, args); // expected-warning@#f6 {{diagnostic behavior may be improved by adding the 'printf' format attribute to the declaration of 'f6'}}
-                        // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:6-[[@LINE-6]]:6}:"__attribute__((format(printf, 1, 0)))"
-}
-
-void f7(const char *out, ... /* args */) // #f7
-{
-    va_list args;
-
-    vscanf(out, &args[0]); // expected-warning@#f7 {{diagnostic behavior may be improved by adding the 'scanf' format attribute to the declaration of 'f7'}}
-                           // CHECK: fix-it:"{{.*}}":{[[@LINE-5]]:6-[[@LINE-5]]:6}:"__attribute__((format(scanf, 1, 0)))"
-}
-
-void f8(const char *out, ... /* args */) // #f8
-{
-    va_list args;
-
-    vscanf(out, &args[0]); // expected-no-warning@#f8
-    vprintf(out, &args[0]); // expected-no-warning@#f8
-}
-
-void f9(const char out[], ... /* args */) // #f9
-{
-    va_list args;
-    char *ch;
-    vprintf(ch, args); // expected-no-warning
-    vsprintf(ch, out, args); // expected-warning@#f9 {{diagnostic behavior may be improved by adding the 'printf' format attribute to the declaration of 'f9'}}
-                             // CHECK: fix-it:"{{.*}}":{[[@LINE-6]]:6-[[@LINE-6]]:6}:"__attribute__((format(printf, 1, 2)))"
-}
-
-void f10(const wchar_t *out, ... /* args */) // #f10
-{
-    va_list args;
-    vscanf(out, args);
-#if __SIZEOF_WCHAR_T__ == 4
-                        // c_diagnostics-warning at -2 {{incompatible pointer types passing 'const wchar_t *' (aka 'const int *') to parameter of type 'const char *'}}
-#else
-                        // c_diagnostics-warning at -4 {{incompatible pointer types passing 'const wchar_t *' (aka 'const unsigned short *') to parameter of type 'const char *'}}
-#endif
-                        // c_diagnostics-note@#vscanf {{passing argument to parameter here}}
-                        // c_diagnostics-warning@#f10 {{diagnostic behavior may be improved by adding the 'scanf' format attribute to the declaration of 'f10'}}
-                        // cpp_diagnostics-error at -8 {{no matching function for call to 'vscanf'}}
-                        // cpp_diagnostics-note@#vscanf {{candidate function not viable: no known conversion from 'const wchar_t *' to 'const char *' for 1st argument}}
-                        // C-CHECK: fix-it:"{{.*}}":{[[@LINE-13]]:6-[[@LINE-13]]:6}:"__attribute__((format(scanf, 1, 2)))"
-}
-
-void f11(const wchar_t *out, ... /* args */) // #f11
-{
-    va_list args;
-    vscanf((const char *) out, args); // expected-warning@#f11 {{diagnostic behavior may be improved by adding the 'scanf' format attribute to the declaration of 'f11'}}
-                                      // CHECK: fix-it:"{{.*}}":{[[@LINE-4]]:6-[[@LINE-4]]:6}:"__attribute__((format(s...
[truncated]

``````````

</details>


https://github.com/llvm/llvm-project/pull/98617


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