[Clang] allow restrict qualifier for array types with pointer types as element types

Author: a-tarasyuk

clang/docs/ReleaseNotes.rst

@@ -332,6 +332,7 @@ C Language Changes
 ------------------
 
 - Extend clang's ``<limits.h>`` to define ``LONG_LONG_*`` macros for Android's bionic.
+- Clang now allows ``restrict`` qualifier for array types with pointer elements (#GH92847).
 
 C2y Feature Support
 ^^^^^^^^^^^^^^^^^^^

clang/lib/Sema/SemaType.cpp

@@ -1595,12 +1595,14 @@ QualType Sema::BuildQualifiedType(QualType T, SourceLocation Loc,
     QualType ProblemTy;
 
     if (T->isAnyPointerType() || T->isReferenceType() ||
-        T->isMemberPointerType()) {
+        T->isMemberPointerType() || T->isArrayType()) {
       QualType EltTy;
       if (T->isObjCObjectPointerType())
         EltTy = T;
       else if (const MemberPointerType *PTy = T->getAs<MemberPointerType>())
         EltTy = PTy->getPointeeType();
+      else if (T->isArrayType())
+        EltTy = Context.getBaseElementType(T);
       else
         EltTy = T->getPointeeType();
 

clang/test/Sema/types.c

@@ -9,20 +9,20 @@ typedef int (*T)[2];
 restrict T x;
 
 typedef int *S[2];
-restrict S y; // expected-error {{restrict requires a pointer or reference ('S' (aka 'int *[2]') is invalid)}}
-
-
+restrict S y;
 
 // int128_t is available.
 int a(void) {
   __int128_t s;
   __uint128_t t;
-}
+} // expected-warning {{non-void function does not return a value}}
+
 // but not a keyword
 int b(void) {
   int __int128_t;
   int __uint128_t;
-}
+} // expected-warning {{non-void function does not return a value}}
+
 // __int128 is a keyword
 int c(void) {
   __int128 i;