QArrayDataPointer: add missing std::invoke call to projection

To ensure the correct invocation of the projection function, this patch
introduces the usage of std::invoke for all accesses to it. This
modification expands the coverage to include cases where the callable
object is a pointer to a member function.

Amends: 7ca633d9a82f90e5bba5e12ba923bfb0a257af63.

Change-Id: If666012d785ac74c8e856ea9be2a46b3307c8a06
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>

1 files changed, 5 insertions, 4 deletions

diff --git a/src/corelib/tools/qarraydatapointer.h b/src/corelib/tools/qarraydatapointer.h
index eb6ceeafee..ad9ca428de 100644
--- a/src/corelib/tools/qarraydatapointer.h
+++ b/src/corelib/tools/qarraydatapointer.h
@@ -334,7 +334,7 @@ public:
         const auto capacityBegin = begin() - offset;
         const auto prependBufferEnd = begin();
 
-        if constexpr (!std::is_nothrow_constructible_v<T, decltype(proj(*first))>) {
+        if constexpr (!std::is_nothrow_constructible_v<T, decltype(std::invoke(proj, *first))>) {
             // If construction can throw, and we have freeSpaceAtBegin(),
             // it's easiest to just clear the container and start fresh.
             // The alternative would be to keep track of two active, disjoint ranges.
@@ -366,7 +366,8 @@ public:
                     size = dst - begin();
                     return;
                 }
-                q20::construct_at(dst, proj(*first)); // construct element in prepend buffer
+                // construct element in prepend buffer
+                q20::construct_at(dst, std::invoke(proj, *first));
                 ++dst;
                 ++first;
             }
@@ -383,12 +384,12 @@ public:
                     break;
                 } else {
                     do {
-                        (*this)->emplace(size, proj(*first));
+                        (*this)->emplace(size, std::invoke(proj, *first));
                     } while (++first != last);
                     return;         // size() is already correct (and dst invalidated)!
                 }
             }
-            *dst = proj(*first);    // overwrite existing element
+            *dst = std::invoke(proj, *first);    // overwrite existing element
             ++dst;
             ++first;
         }