[clang] Diagnose problematic uses of constructor/destructor attribute (PR #67360)

Aaron Ballman via cfe-commits cfe-commits at lists.llvm.org
Mon Sep 25 12:08:22 PDT 2023


https://github.com/AaronBallman created https://github.com/llvm/llvm-project/pull/67360

Functions with these attributes will be automatically called before main() or after main() exits gracefully, which means the functions should not accept arguments or have a returned value (nothing can provide an argument to the call in these cases, and nothing can use the returned value), nor should they be allowed on a non-static member function in C++.

Additionally, these reuse the same priority logic as the init_priority attribute which explicitly reserved priorty values <= 100 or > 65535. So we now diagnose use of reserved priorities the same as we do for the init_priority attribute.

>From 6e9bcfa7fc5eb3da4592909b9e199215064df700 Mon Sep 17 00:00:00 2001
From: Aaron Ballman <aaron at aaronballman.com>
Date: Mon, 25 Sep 2023 15:03:56 -0400
Subject: [PATCH] Diagnose problematic uses of constructor/destructor attribute

Functions with these attributes will be automatically called before
main() or after main() exits gracefully, which means the functions
should not accept arguments or have a returned value (nothing can
provide an argument to the call in these cases, and nothing can use
the returned value), nor should they be allowed on a non-static member
function in C++.

Additionally, these reuse the same priority logic as the init_priority
attribute which explicitly reserved priorty values <= 100 or > 65535.
So we now diagnose use of reserved priorities the same as we do for the
init_priority attribute.
---
 clang/docs/ReleaseNotes.rst                   |  5 ++
 .../clang/Basic/DiagnosticSemaKinds.td        |  5 ++
 clang/lib/Sema/SemaDeclAttr.cpp               | 74 +++++++++++++------
 clang/test/CodeGen/2008-03-03-CtorAttrType.c  |  4 +-
 .../PowerPC/aix-constructor-attribute.c       | 20 ++---
 .../PowerPC/aix-destructor-attribute.c        | 30 +++-----
 .../CodeGenCXX/aix-constructor-attribute.cpp  | 20 ++---
 .../CodeGenCXX/aix-destructor-attribute.cpp   | 36 ++++-----
 clang/test/Sema/constructor-attribute.c       | 60 ++++++++++++---
 9 files changed, 147 insertions(+), 107 deletions(-)

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 294b77a3e260908..a9ef2e2c378c7e3 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -171,6 +171,11 @@ Attribute Changes in Clang
   automatic diagnostic to use parameters of types that the format style
   supports but that are never the result of default argument promotion, such as
   ``float``. (`#59824: <https://github.com/llvm/llvm-project/issues/59824>`_)
+- The ``constructor`` and ``destructor`` attributes now diagnose when:
+  - the priority is not between 101 and 65535, inclusive,
+  - the function it is applied to accepts arguments or has a non-void return
+    type, or
+  - the function it is applied to is a non-static member function (C++).
 
 Improvements to Clang's diagnostics
 -----------------------------------
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index f4eb02fd9570c2f..1c522500fedcf6d 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -3176,6 +3176,11 @@ def err_alignas_underaligned : Error<
   "requested alignment is less than minimum alignment of %1 for type %0">;
 def warn_aligned_attr_underaligned : Warning<err_alignas_underaligned.Summary>,
   InGroup<IgnoredAttributes>;
+def err_ctor_dtor_attr_on_non_void_func : Error<
+  "%0 attribute can only be applied to a function which accepts no arguments "
+  "and has a 'void' return type">;
+def err_ctor_dtor_member_func : Error<
+  "%0 attribute cannot be applied to a member function">;
 def err_attribute_sizeless_type : Error<
   "%0 attribute cannot be applied to sizeless type %1">;
 def err_attribute_argument_n_type : Error<
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index 090a54eedaa07d0..79a73ba4618c85d 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -2352,26 +2352,61 @@ static void handleUnusedAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   D->addAttr(::new (S.Context) UnusedAttr(S.Context, AL));
 }
 
-static void handleConstructorAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
-  uint32_t priority = ConstructorAttr::DefaultPriority;
+static bool diagnoseInvalidPriority(Sema &S, uint32_t Priority,
+                                    const ParsedAttr &A,
+                                    SourceLocation PriorityLoc) {
+  // Only perform the priority check if the attribute is outside of a system
+  // header. Values <= 100 are reserved for the implementation, and libc++
+  // benefits from being able to specify values in that range.
+  if ((Priority < 101 || Priority > 65535) &&
+      !S.getSourceManager().isInSystemHeader(A.getLoc())) {
+    S.Diag(A.getLoc(), diag::err_attribute_argument_out_of_range)
+        << PriorityLoc << A << 101 << 65535;
+    A.setInvalid();
+    return true;
+  }
+  return false;
+}
+
+template <typename CtorDtorAttr>
+static void handleCtorDtorAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
+  uint32_t Priority = CtorDtorAttr::DefaultPriority;
   if (S.getLangOpts().HLSL && AL.getNumArgs()) {
     S.Diag(AL.getLoc(), diag::err_hlsl_init_priority_unsupported);
     return;
   }
-  if (AL.getNumArgs() &&
-      !checkUInt32Argument(S, AL, AL.getArgAsExpr(0), priority))
-    return;
 
-  D->addAttr(::new (S.Context) ConstructorAttr(S.Context, AL, priority));
-}
+  // If we're given an argument for the priority, check that it's valid.
+  if (AL.getNumArgs()) {
+    if (!checkUInt32Argument(S, AL, AL.getArgAsExpr(0), Priority))
+      return;
 
-static void handleDestructorAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
-  uint32_t priority = DestructorAttr::DefaultPriority;
-  if (AL.getNumArgs() &&
-      !checkUInt32Argument(S, AL, AL.getArgAsExpr(0), priority))
+    // Ensure the priority is in a reasonable range.
+    if (diagnoseInvalidPriority(S, Priority, AL,
+                                AL.getArgAsExpr(0)->getExprLoc()))
+      return;
+  }
+
+  // Ensure the function we're attaching to is something that is sensible to
+  // automatically call before or after main(); it should accept no arguments
+  // and return no value (but it is not an error because it is theoretically
+  // possible to call the function during normal program execution and pass it
+  // valid values). It also cannot be a member function. We allow K&R C
+  // functions because that's a difficult edge case where it depends on how the
+  // function is defined as to whether it does or does not expect arguments.
+  auto *FD = cast<FunctionDecl>(D);
+  if (!FD->getReturnType()->isVoidType() ||
+      (FD->hasPrototype() && FD->getNumParams() != 0)) {
+    S.Diag(AL.getLoc(), diag::err_ctor_dtor_attr_on_non_void_func)
+        << AL << FD->getSourceRange();
     return;
+  } else if (auto *MD = dyn_cast<CXXMethodDecl>(FD); MD && MD->isInstance()) {
+    S.Diag(AL.getLoc(), diag::err_ctor_dtor_member_func)
+        << AL << FD->getSourceRange();
+    return;
+  }
 
-  D->addAttr(::new (S.Context) DestructorAttr(S.Context, AL, priority));
+  D->addAttr(::new (S.Context) CtorDtorAttr(S.Context, AL, Priority));
 }
 
 template <typename AttrTy>
@@ -3888,16 +3923,9 @@ static void handleInitPriorityAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
     return;
   }
 
-  // Only perform the priority check if the attribute is outside of a system
-  // header. Values <= 100 are reserved for the implementation, and libc++
-  // benefits from being able to specify values in that range.
-  if ((prioritynum < 101 || prioritynum > 65535) &&
-      !S.getSourceManager().isInSystemHeader(AL.getLoc())) {
-    S.Diag(AL.getLoc(), diag::err_attribute_argument_out_of_range)
-        << E->getSourceRange() << AL << 101 << 65535;
-    AL.setInvalid();
+  if (diagnoseInvalidPriority(S, prioritynum, AL, E->getExprLoc()))
     return;
-  }
+
   D->addAttr(::new (S.Context) InitPriorityAttr(S.Context, AL, prioritynum));
 }
 
@@ -8930,13 +8958,13 @@ ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D, const ParsedAttr &AL,
     handlePassObjectSizeAttr(S, D, AL);
     break;
   case ParsedAttr::AT_Constructor:
-      handleConstructorAttr(S, D, AL);
+    handleCtorDtorAttr<ConstructorAttr>(S, D, AL);
     break;
   case ParsedAttr::AT_Deprecated:
     handleDeprecatedAttr(S, D, AL);
     break;
   case ParsedAttr::AT_Destructor:
-      handleDestructorAttr(S, D, AL);
+    handleCtorDtorAttr<DestructorAttr>(S, D, AL);
     break;
   case ParsedAttr::AT_EnableIf:
     handleEnableIfAttr(S, D, AL);
diff --git a/clang/test/CodeGen/2008-03-03-CtorAttrType.c b/clang/test/CodeGen/2008-03-03-CtorAttrType.c
index dbd7bc0a7270953..efc219bf85e6f4e 100644
--- a/clang/test/CodeGen/2008-03-03-CtorAttrType.c
+++ b/clang/test/CodeGen/2008-03-03-CtorAttrType.c
@@ -1,6 +1,4 @@
 // RUN: %clang_cc1 %s -emit-llvm -o - | grep llvm.global_ctors
-int __attribute__((constructor)) foo(void) {
-  return 0;
-}
+void __attribute__((constructor)) foo(void) {}
 void __attribute__((constructor)) bar(void) {}
 
diff --git a/clang/test/CodeGen/PowerPC/aix-constructor-attribute.c b/clang/test/CodeGen/PowerPC/aix-constructor-attribute.c
index 7cd72a3276936ff..031deeb3ab257a8 100644
--- a/clang/test/CodeGen/PowerPC/aix-constructor-attribute.c
+++ b/clang/test/CodeGen/PowerPC/aix-constructor-attribute.c
@@ -7,18 +7,10 @@
 
 // CHECK: @llvm.global_ctors = appending global [3 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 65535, ptr @foo3, ptr null }, { i32, ptr, ptr } { i32 180, ptr @foo2, ptr null }, { i32, ptr, ptr } { i32 180, ptr @foo, ptr null }]
 
-int foo(void) __attribute__((constructor(180)));
-int foo2(void) __attribute__((constructor(180)));
-int foo3(void) __attribute__((constructor(65535)));
+void foo(void) __attribute__((constructor(180)));
+void foo2(void) __attribute__((constructor(180)));
+void foo3(void) __attribute__((constructor(65535)));
 
-int foo3(void) {
-  return 3;
-}
-
-int foo2(void) {
-  return 2;
-}
-
-int foo(void) {
-  return 1;
-}
+void foo3(void) {}
+void foo2(void) {}
+void foo(void) {}
diff --git a/clang/test/CodeGen/PowerPC/aix-destructor-attribute.c b/clang/test/CodeGen/PowerPC/aix-destructor-attribute.c
index cfb1fd7b0171a41..6c49b0f638e760d 100644
--- a/clang/test/CodeGen/PowerPC/aix-destructor-attribute.c
+++ b/clang/test/CodeGen/PowerPC/aix-destructor-attribute.c
@@ -12,28 +12,20 @@
 // RUN:     -fno-use-cxa-atexit -fregister-global-dtors-with-atexit < %s | \
 // RUN:   FileCheck --check-prefix=REGISTER %s
 
-int bar(void) __attribute__((destructor(100)));
-int bar2(void) __attribute__((destructor(65535)));
-int bar3(int) __attribute__((destructor(65535)));
+void bar(void) __attribute__((destructor(101)));
+void bar2(void) __attribute__((destructor(65535)));
+void bar3(void) __attribute__((destructor(65535)));
 
-int bar(void) {
-  return 1;
-}
+void bar(void) {}
+void bar2(void) {}
+void bar3(void) {}
 
-int bar2(void) {
-  return 2;
-}
+// NO-REGISTER: @llvm.global_dtors = appending global [3 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 101, ptr @bar, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @bar2, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @bar3, ptr null }]
 
-int bar3(int a) {
-  return a;
-}
+// REGISTER: @llvm.global_ctors = appending global [2 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 101, ptr @__GLOBAL_init_101, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @__GLOBAL_init_65535, ptr null }]
+// REGISTER: @llvm.global_dtors = appending global [2 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 101, ptr @__GLOBAL_cleanup_101, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @__GLOBAL_cleanup_65535, ptr null }]
 
-// NO-REGISTER: @llvm.global_dtors = appending global [3 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 100, ptr @bar, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @bar2, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @bar3, ptr null }]
-
-// REGISTER: @llvm.global_ctors = appending global [2 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 100, ptr @__GLOBAL_init_100, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @__GLOBAL_init_65535, ptr null }]
-// REGISTER: @llvm.global_dtors = appending global [2 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 100, ptr @__GLOBAL_cleanup_100, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @__GLOBAL_cleanup_65535, ptr null }]
-
-// REGISTER: define internal void @__GLOBAL_init_100() [[ATTR:#[0-9]+]] {
+// REGISTER: define internal void @__GLOBAL_init_101() [[ATTR:#[0-9]+]] {
 // REGISTER: entry:
 // REGISTER:   %0 = call i32 @atexit(ptr @bar)
 // REGISTER:   ret void
@@ -46,7 +38,7 @@ int bar3(int a) {
 // REGISTER:   ret void
 // REGISTER: }
 
-// REGISTER: define internal void @__GLOBAL_cleanup_100() [[ATTR:#[0-9]+]] {
+// REGISTER: define internal void @__GLOBAL_cleanup_101() [[ATTR:#[0-9]+]] {
 // REGISTER: entry:
 // REGISTER:   %0 = call i32 @unatexit(ptr @bar)
 // REGISTER:   %needs_destruct = icmp eq i32 %0, 0
diff --git a/clang/test/CodeGenCXX/aix-constructor-attribute.cpp b/clang/test/CodeGenCXX/aix-constructor-attribute.cpp
index 9f1191278fcd34c..84c2b6722628344 100644
--- a/clang/test/CodeGenCXX/aix-constructor-attribute.cpp
+++ b/clang/test/CodeGenCXX/aix-constructor-attribute.cpp
@@ -8,9 +8,9 @@
 // CHECK: @llvm.global_ctors = appending global [4 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 65535, ptr @_Z4foo3v, ptr null }, { i32, ptr, ptr } { i32 180, ptr @_Z4foo2v, ptr null }, { i32, ptr, ptr } { i32 180, ptr @_Z3foov, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @_GLOBAL__sub_I__, ptr null }]
 // CHECK: @llvm.global_dtors = appending global [1 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 65535, ptr @_GLOBAL__D_a, ptr null }]
 
-int foo() __attribute__((constructor(180)));
-int foo2() __attribute__((constructor(180)));
-int foo3() __attribute__((constructor(65535)));
+void foo() __attribute__((constructor(180)));
+void foo2() __attribute__((constructor(180)));
+void foo3() __attribute__((constructor(65535)));
 
 struct Test {
 public:
@@ -18,14 +18,6 @@ struct Test {
   ~Test() {}
 } t;
 
-int foo3() {
-  return 3;
-}
-
-int foo2() {
-  return 2;
-}
-
-int foo() {
-  return 1;
-}
+void foo3() {}
+void foo2() {}
+void foo() {}
diff --git a/clang/test/CodeGenCXX/aix-destructor-attribute.cpp b/clang/test/CodeGenCXX/aix-destructor-attribute.cpp
index 5ebea7a997c9db1..2782c7ee74939e5 100644
--- a/clang/test/CodeGenCXX/aix-destructor-attribute.cpp
+++ b/clang/test/CodeGenCXX/aix-destructor-attribute.cpp
@@ -17,29 +17,21 @@ struct test {
   ~test();
 } t;
 
-int bar() __attribute__((destructor(100)));
-int bar2() __attribute__((destructor(65535)));
-int bar3(int) __attribute__((destructor(65535)));
+void bar() __attribute__((destructor(101)));
+void bar2() __attribute__((destructor(65535)));
+void bar3() __attribute__((destructor(65535)));
 
-int bar() {
-  return 1;
-}
-
-int bar2() {
-  return 2;
-}
-
-int bar3(int a) {
-  return a;
-}
+void bar() {}
+void bar2() {}
+void bar3() {}
 
 // NO-REGISTER: @llvm.global_ctors = appending global [1 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 65535, ptr @_GLOBAL__sub_I__, ptr null }]
-// NO-REGISTER: @llvm.global_dtors = appending global [4 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 100, ptr @_Z3barv, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @_Z4bar2v, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @_Z4bar3i, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @_GLOBAL__D_a, ptr null }]
+// NO-REGISTER: @llvm.global_dtors = appending global [4 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 101, ptr @_Z3barv, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @_Z4bar2v, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @_Z4bar3v, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @_GLOBAL__D_a, ptr null }]
 
-// REGISTER: @llvm.global_ctors = appending global [3 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 65535, ptr @_GLOBAL__sub_I__, ptr null }, { i32, ptr, ptr } { i32 100, ptr @__GLOBAL_init_100, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @__GLOBAL_init_65535, ptr null }]
-// REGISTER: @llvm.global_dtors = appending global [3 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 65535, ptr @_GLOBAL__D_a, ptr null }, { i32, ptr, ptr } { i32 100, ptr @__GLOBAL_cleanup_100, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @__GLOBAL_cleanup_65535, ptr null }]
+// REGISTER: @llvm.global_ctors = appending global [3 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 65535, ptr @_GLOBAL__sub_I__, ptr null }, { i32, ptr, ptr } { i32 101, ptr @__GLOBAL_init_101, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @__GLOBAL_init_65535, ptr null }]
+// REGISTER: @llvm.global_dtors = appending global [3 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 65535, ptr @_GLOBAL__D_a, ptr null }, { i32, ptr, ptr } { i32 101, ptr @__GLOBAL_cleanup_101, ptr null }, { i32, ptr, ptr } { i32 65535, ptr @__GLOBAL_cleanup_65535, ptr null }]
 
-// REGISTER: define internal void @__GLOBAL_init_100() [[ATTR:#[0-9]+]] {
+// REGISTER: define internal void @__GLOBAL_init_101() [[ATTR:#[0-9]+]] {
 // REGISTER: entry:
 // REGISTER:   %0 = call i32 @atexit(ptr @_Z3barv)
 // REGISTER:   ret void
@@ -48,11 +40,11 @@ int bar3(int a) {
 // REGISTER: define internal void @__GLOBAL_init_65535() [[ATTR:#[0-9]+]] {
 // REGISTER: entry:
 // REGISTER:   %0 = call i32 @atexit(ptr @_Z4bar2v)
-// REGISTER:   %1 = call i32 @atexit(ptr @_Z4bar3i)
+// REGISTER:   %1 = call i32 @atexit(ptr @_Z4bar3v)
 // REGISTER:   ret void
 // REGISTER: }
 
-// REGISTER: define internal void @__GLOBAL_cleanup_100() [[ATTR:#[0-9]+]] {
+// REGISTER: define internal void @__GLOBAL_cleanup_101() [[ATTR:#[0-9]+]] {
 // REGISTER: entry:
 // REGISTER:   %0 = call i32 @unatexit(ptr @_Z3barv)
 // REGISTER:   %needs_destruct = icmp eq i32 %0, 0
@@ -68,12 +60,12 @@ int bar3(int a) {
 
 // REGISTER: define internal void @__GLOBAL_cleanup_65535() [[ATTR:#[0-9]+]] {
 // REGISTER: entry:
-// REGISTER:   %0 = call i32 @unatexit(ptr @_Z4bar3i)
+// REGISTER:   %0 = call i32 @unatexit(ptr @_Z4bar3v)
 // REGISTER:   %needs_destruct = icmp eq i32 %0, 0
 // REGISTER:   br i1 %needs_destruct, label %destruct.call, label %unatexit.call
 
 // REGISTER: destruct.call:
-// REGISTER:   call void @_Z4bar3i()
+// REGISTER:   call void @_Z4bar3v()
 // REGISTER:   br label %unatexit.call
 
 // REGISTER: unatexit.call:
diff --git a/clang/test/Sema/constructor-attribute.c b/clang/test/Sema/constructor-attribute.c
index 2317c7735bda586..8df5ac42378bdd8 100644
--- a/clang/test/Sema/constructor-attribute.c
+++ b/clang/test/Sema/constructor-attribute.c
@@ -1,16 +1,52 @@
 // RUN: %clang_cc1 -fsyntax-only -verify -Wno-strict-prototypes %s
+// RUN: %clang_cc1 -fsyntax-only -verify -x c++ %s
 
-int x __attribute__((constructor)); // expected-warning {{'constructor' attribute only applies to functions}}
-int f(void) __attribute__((constructor));
-int f(void) __attribute__((constructor(1)));
-int f(void) __attribute__((constructor(1,2))); // expected-error {{'constructor' attribute takes no more than 1 argument}}
-int f(void) __attribute__((constructor(1.0))); // expected-error {{'constructor' attribute requires an integer constant}}
-int f(void) __attribute__((constructor(0x100000000))); // expected-error {{integer constant expression evaluates to value 4294967296 that cannot be represented in a 32-bit unsigned integer type}}
+int x1 __attribute__((constructor)); // expected-warning {{'constructor' attribute only applies to functions}}
+void f(void) __attribute__((constructor));
+void f(void) __attribute__((constructor(1)));   // expected-error {{'constructor' attribute requires integer constant between 101 and 65535 inclusive}}
+void f(void) __attribute__((constructor(1,2))); // expected-error {{'constructor' attribute takes no more than 1 argument}}
+void f(void) __attribute__((constructor(1.0))); // expected-error {{'constructor' attribute requires an integer constant}}
+void f(void) __attribute__((constructor(0x100000000))); // expected-error {{integer constant expression evaluates to value 4294967296 that cannot be represented in a 32-bit unsigned integer type}}
+void f(void) __attribute__((constructor(101)));
 
-int x __attribute__((destructor)); // expected-warning {{'destructor' attribute only applies to functions}}
-int f(void) __attribute__((destructor));
-int f(void) __attribute__((destructor(1)));
-int f(void) __attribute__((destructor(1,2))); // expected-error {{'destructor' attribute takes no more than 1 argument}}
-int f(void) __attribute__((destructor(1.0))); // expected-error {{'destructor' attribute requires an integer constant}}
+int x2 __attribute__((destructor)); // expected-warning {{'destructor' attribute only applies to functions}}
+void f(void) __attribute__((destructor));
+void f(void) __attribute__((destructor(1)));   // expected-error {{'destructor' attribute requires integer constant between 101 and 65535 inclusive}}
+void f(void) __attribute__((destructor(1,2))); // expected-error {{'destructor' attribute takes no more than 1 argument}}
+void f(void) __attribute__((destructor(1.0))); // expected-error {{'destructor' attribute requires an integer constant}}
+void f(void) __attribute__((destructor(101)));
 
-void knr() __attribute__((constructor));
+void knr1() __attribute__((constructor));
+void knr2() __attribute__((destructor));
+
+// Require a void return type
+int g(void) __attribute__((constructor)); // expected-error {{'constructor' attribute can only be applied to a function which accepts no arguments and has a 'void' return type}}
+int h(void) __attribute__((destructor));  // expected-error {{'destructor' attribute can only be applied to a function which accepts no arguments and has a 'void' return type}}
+
+// Require no parameters
+void i(int v) __attribute__((constructor)); // expected-error {{'constructor' attribute can only be applied to a function which accepts no arguments and has a 'void' return type}}
+void j(int v) __attribute__((destructor));  // expected-error {{'destructor' attribute can only be applied to a function which accepts no arguments and has a 'void' return type}}
+
+#ifdef __cplusplus
+struct S {
+  // Not allowed on a nonstatic member function, but is allowed on a static
+  // member function so long as it has no args/void return type.
+  void mem1() __attribute__((constructor)); // expected-error {{'constructor' attribute cannot be applied to a member function}}
+  void mem2() __attribute__((destructor));  // expected-error {{'destructor' attribute cannot be applied to a member function}}
+
+  static void nonmem1() __attribute__((constructor));
+  static void nonmem2() __attribute__((destructor));
+
+  static int nonmem3() __attribute__((constructor)); // expected-error {{'constructor' attribute can only be applied to a function which accepts no arguments and has a 'void' return type}}
+  static int nonmem4() __attribute__((destructor));  // expected-error {{'destructor' attribute can only be applied to a function which accepts no arguments and has a 'void' return type}}
+
+  static void nonmem5(int) __attribute__((constructor)); // expected-error {{'constructor' attribute can only be applied to a function which accepts no arguments and has a 'void' return type}}
+  static void nonmem6(int) __attribute__((destructor));  // expected-error {{'destructor' attribute can only be applied to a function which accepts no arguments and has a 'void' return type}}
+};
+#endif // __cplusplus
+
+# 1 "source.c" 1 3
+// Can use reserved priorities within a system header
+void f(void) __attribute__((constructor(1)));
+void f(void) __attribute__((destructor(1)));
+# 1 "source.c" 2



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