commit 0163bbaaef119ef9e98c4b3dcba159609f77c818
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Wed Aug 25 22:24:54 2021

    libstdc++: Fix non-reserved names in <valarray>
    
    Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
    
    libstdc++-v3/ChangeLog:
    
            * include/std/valarray: Uglify 'func' parameters.
            * testsuite/17_intro/names.cc: Add 'func' to checks.

diff --git a/libstdc++-v3/include/std/valarray b/libstdc++-v3/include/std/valarray
index ad3e14ebe52..5adc94282ee 100644
--- a/libstdc++-v3/include/std/valarray
+++ b/libstdc++-v3/include/std/valarray
@@ -536,25 +536,25 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
        *  @brief  Apply a function to the array.
        *
        *  Returns a new valarray with elements assigned to the result of
-       *  applying func to the corresponding element of this array.  The new
+       *  applying __func to the corresponding element of this array.  The new
        *  array has the same size as this one.
        *
-       *  @param  func  Function of Tp returning Tp to apply.
+       *  @param  __func  Function of Tp returning Tp to apply.
        *  @return  New valarray with transformed elements.
        */
-      _Expr<_ValFunClos<_ValArray, _Tp>, _Tp> apply(_Tp func(_Tp)) const;
+      _Expr<_ValFunClos<_ValArray, _Tp>, _Tp> apply(_Tp __func(_Tp)) const;
 
       /**
        *  @brief  Apply a function to the array.
        *
        *  Returns a new valarray with elements assigned to the result of
-       *  applying func to the corresponding element of this array.  The new
+       *  applying __func to the corresponding element of this array.  The new
        *  array has the same size as this one.
        *
-       *  @param  func  Function of const Tp& returning Tp to apply.
+       *  @param  __func  Function of const Tp& returning Tp to apply.
        *  @return  New valarray with transformed elements.
        */
-      _Expr<_RefFunClos<_ValArray, _Tp>, _Tp> apply(_Tp func(const _Tp&)) const;
+      _Expr<_RefFunClos<_ValArray, _Tp>, _Tp> apply(_Tp __func(const _Tp&)) const;
 
       /**
        *  @brief  Resize array.
@@ -1062,18 +1062,18 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
   template<class _Tp>
     inline _Expr<_ValFunClos<_ValArray, _Tp>, _Tp>
-    valarray<_Tp>::apply(_Tp func(_Tp)) const
+    valarray<_Tp>::apply(_Tp __func(_Tp)) const
     {
       typedef _ValFunClos<_ValArray, _Tp> _Closure;
-      return _Expr<_Closure, _Tp>(_Closure(*this, func));
+      return _Expr<_Closure, _Tp>(_Closure(*this, __func));
     }
 
   template<class _Tp>
     inline _Expr<_RefFunClos<_ValArray, _Tp>, _Tp>
-    valarray<_Tp>::apply(_Tp func(const _Tp &)) const
+    valarray<_Tp>::apply(_Tp __func(const _Tp &)) const
     {
       typedef _RefFunClos<_ValArray, _Tp> _Closure;
-      return _Expr<_Closure, _Tp>(_Closure(*this, func));
+      return _Expr<_Closure, _Tp>(_Closure(*this, __func));
     }
 
 #define _DEFINE_VALARRAY_UNARY_OPERATOR(_Op, _Name)                     \
diff --git a/libstdc++-v3/testsuite/17_intro/names.cc b/libstdc++-v3/testsuite/17_intro/names.cc
index aca7a8e5812..3cbe0d2da54 100644
--- a/libstdc++-v3/testsuite/17_intro/names.cc
+++ b/libstdc++-v3/testsuite/17_intro/names.cc
@@ -106,6 +106,7 @@
 #endif
 #define z (
 
+#define func (
 #define tmp (
 
 #if __cplusplus < 201103L