Index: flang/docs/Extensions.md
===================================================================
--- flang/docs/Extensions.md
+++ flang/docs/Extensions.md
@@ -295,6 +295,9 @@
   by a line continuation in free form, the second quotation mark
   may appear at the beginning of the continuation line without an
   ampersand, althought one is required by the standard.
+* Unrestricted `INTRINSIC` functions are accepted for use in
+  `PROCEDURE` statements in generic interfaces, as in some other
+  compilers.
 
 ### Extensions supported when enabled by options
 
Index: flang/lib/Semantics/check-declarations.cpp
===================================================================
--- flang/lib/Semantics/check-declarations.cpp
+++ flang/lib/Semantics/check-declarations.cpp
@@ -1726,12 +1726,25 @@
       continue;
     }
     if (specific.attrs().test(Attr::INTRINSIC)) {
-      if (auto *msg{messages_.Say(specific.name(),
-              "Specific procedure '%s' of generic interface '%s' may not be INTRINSIC"_err_en_US,
-              specific.name(), generic.name())}) {
-        msg->Attach(generic.name(), "Definition of '%s'"_en_US, generic.name());
+      // GNU Fortran allows INTRINSIC procedures in generics.
+      auto intrinsic{context_.intrinsics().IsSpecificIntrinsicFunction(
+          specific.name().ToString())};
+      if (intrinsic && !intrinsic->isRestrictedSpecific) {
+        if (auto *msg{messages_.Say(specific.name(),
+                "Specific procedure '%s' of generic interface '%s' should not be INTRINSIC"_port_en_US,
+                specific.name(), generic.name())}) {
+          msg->Attach(
+              generic.name(), "Definition of '%s'"_en_US, generic.name());
+        }
+      } else {
+        if (auto *msg{messages_.Say(specific.name(),
+                "Procedure '%s' of generic interface '%s' is INTRINSIC but not an unrestricted specific intrinsic function"_port_en_US,
+                specific.name(), generic.name())}) {
+          msg->Attach(
+              generic.name(), "Definition of '%s'"_en_US, generic.name());
+        }
+        continue;
       }
-      continue;
     }
     if (IsStmtFunction(specific)) {
       if (auto *msg{messages_.Say(specific.name(),
Index: flang/lib/Semantics/expression.cpp
===================================================================
--- flang/lib/Semantics/expression.cpp
+++ flang/lib/Semantics/expression.cpp
@@ -2608,10 +2608,10 @@
     resolution = symbol;
   }
   if (!resolution || resolution->attrs().test(semantics::Attr::INTRINSIC)) {
-    // Not generic, or no resolution; may be intrinsic
+    auto name{resolution ? resolution->name() : ultimate.name()};
     if (std::optional<SpecificCall> specificCall{context_.intrinsics().Probe(
-            CallCharacteristics{ultimate.name().ToString(), isSubroutine},
-            arguments, GetFoldingContext())}) {
+            CallCharacteristics{name.ToString(), isSubroutine}, arguments,
+            GetFoldingContext())}) {
       CheckBadExplicitType(*specificCall, *symbol);
       return CalleeAndArguments{
           ProcedureDesignator{std::move(specificCall->specificIntrinsic)},
Index: flang/lib/Semantics/resolve-names.cpp
===================================================================
--- flang/lib/Semantics/resolve-names.cpp
+++ flang/lib/Semantics/resolve-names.cpp
@@ -4619,15 +4619,27 @@
       Say(symbol.name(),
           "Symbol '%s' cannot have both EXTERNAL and INTRINSIC attributes"_err_en_US,
           symbol.name());
-    } else if (symbol.GetType()) {
-      // These warnings are worded so that they should make sense in either
-      // order.
-      Say(symbol.name(),
-          "Explicit type declaration ignored for intrinsic function '%s'"_warn_en_US,
-          symbol.name())
-          .Attach(name.source,
-              "INTRINSIC statement for explicitly-typed '%s'"_en_US,
-              name.source);
+    } else {
+      if (symbol.GetType()) {
+        // These warnings are worded so that they should make sense in either
+        // order.
+        Say(symbol.name(),
+            "Explicit type declaration ignored for intrinsic function '%s'"_warn_en_US,
+            symbol.name())
+            .Attach(name.source,
+                "INTRINSIC statement for explicitly-typed '%s'"_en_US,
+                name.source);
+      }
+      if (!symbol.test(Symbol::Flag::Function) &&
+          !symbol.test(Symbol::Flag::Subroutine)) {
+        if (context().intrinsics().IsIntrinsicFunction(
+                name.source.ToString())) {
+          symbol.set(Symbol::Flag::Function);
+        } else if (context().intrinsics().IsIntrinsicSubroutine(
+                       name.source.ToString())) {
+          symbol.set(Symbol::Flag::Subroutine);
+        }
+      }
     }
   }
   return false;
Index: flang/test/Semantics/call16.f90
===================================================================
--- flang/test/Semantics/call16.f90
+++ flang/test/Semantics/call16.f90
@@ -4,9 +4,9 @@
 
 subroutine test(x, t)
  intrinsic :: sin, cpu_time
- !ERROR: Cannot use intrinsic function 'sin' as a subroutine
+ !ERROR: Cannot call intrinsic function 'sin' as a subroutine
  call sin(x)
- !ERROR: Cannot use intrinsic subroutine 'cpu_time' as a function
+ !ERROR: Cannot call intrinsic subroutine 'cpu_time' as a function
  x = cpu_time(t)
 end subroutine
 
Index: flang/test/Semantics/generic06.f90
===================================================================
--- flang/test/Semantics/generic06.f90
+++ flang/test/Semantics/generic06.f90
@@ -1,11 +1,11 @@
 ! RUN: %python %S/test_errors.py %s %flang_fc1
 module m
-  !ERROR: Specific procedure 'sin' of generic interface 'yintercept' may not be INTRINSIC
+  !PORTABILITY: Specific procedure 'sin' of generic interface 'yintercept' should not be INTRINSIC
   intrinsic sin
   interface yIntercept
     procedure sin
   end interface
-  !ERROR: Specific procedure 'cos' of generic interface 'xintercept' may not be INTRINSIC
+  !PORTABILITY: Specific procedure 'cos' of generic interface 'xintercept' should not be INTRINSIC
   intrinsic cos
   generic :: xIntercept => cos
 end module