From 4d6759aca47359f21c8168d76aebbde2fcff727d Mon Sep 17 00:00:00 2001
From: Nathaniel Filardo <nwf20@cl.cam.ac.uk>
Date: Wed, 4 Dec 2019 16:53:35 +0000
Subject: [PATCH] Make "pal_supports" not a function

But rather a template vardecl, as per C++14
---
 src/mem/alloc.h      | 2 +-
 src/mem/chunkmap.h   | 2 +-
 src/mem/largealloc.h | 4 ++--
 src/pal/pal.h        | 5 +----
 4 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/src/mem/alloc.h b/src/mem/alloc.h
index 1260e9c..d483f7a 100644
--- a/src/mem/alloc.h
+++ b/src/mem/alloc.h
@@ -1120,7 +1120,7 @@ namespace snmalloc
           else if constexpr (decommit_strategy == DecommitSuperLazy)
           {
             static_assert(
-              pal_supports<LowMemoryNotification, MemoryProvider>(),
+              pal_supports<LowMemoryNotification, MemoryProvider>,
               "A lazy decommit strategy cannot be implemented on platforms "
               "without low memory notifications");
           }
diff --git a/src/mem/chunkmap.h b/src/mem/chunkmap.h
index b261293..1cb2edf 100644
--- a/src/mem/chunkmap.h
+++ b/src/mem/chunkmap.h
@@ -47,7 +47,7 @@ namespace snmalloc
 // Use flat map is under a single node.
 #  define SNMALLOC_MAX_FLATPAGEMAP_SIZE PAGEMAP_NODE_SIZE
 #endif
-  static constexpr bool USE_FLATPAGEMAP = pal_supports<LazyCommit>() ||
+  static constexpr bool USE_FLATPAGEMAP = pal_supports<LazyCommit> ||
     (SNMALLOC_MAX_FLATPAGEMAP_SIZE >=
      sizeof(FlatPagemap<SUPERSLAB_BITS, uint8_t>));
 
diff --git a/src/mem/largealloc.h b/src/mem/largealloc.h
index f7fcc92..c70a9b9 100644
--- a/src/mem/largealloc.h
+++ b/src/mem/largealloc.h
@@ -190,7 +190,7 @@ namespace snmalloc
     SNMALLOC_FAST_PATH
     uint64_t low_memory_epoch()
     {
-      if constexpr (pal_supports<LowMemoryNotification, PAL>())
+      if constexpr (pal_supports<LowMemoryNotification, PAL>)
       {
         return PAL::low_memory_epoch();
       }
@@ -203,7 +203,7 @@ namespace snmalloc
     template<bool committed>
     void* reserve(size_t* size, size_t align) noexcept
     {
-      if constexpr (pal_supports<AlignedAllocation, PAL>())
+      if constexpr (pal_supports<AlignedAllocation, PAL>)
       {
         return PAL::template reserve<committed>(size, align);
       }
diff --git a/src/pal/pal.h b/src/pal/pal.h
index 8b967b1..11ae017 100644
--- a/src/pal/pal.h
+++ b/src/pal/pal.h
@@ -61,8 +61,5 @@ namespace snmalloc
    * Query whether the PAL supports a specific feature.
    */
   template<PalFeatures F, typename PAL = Pal>
-  constexpr static bool pal_supports()
-  {
-    return (PAL::pal_features & F) == F;
-  }
+  constexpr static bool pal_supports = (PAL::pal_features & F) == F;
 } // namespace snmalloc