Bug 1776463 - Use C++17 inline variable for CountingAllocatorBase::sAmount. r=xpcom-reviewers,nika

Differential Revision: https://phabricator.services.mozilla.com/D159360

extensions/spellcheck/hunspell/glue/moz.build

@@ -37,9 +37,3 @@ EXPORTS.mozilla += [
     "RemoteSpellCheckEngineChild.h",
     "RemoteSpellCheckEngineParent.h",
 ]
-
-if CONFIG["CC_TYPE"] in ("clang", "clang-cl"):
-    CXXFLAGS += [
-        # We force-include mozHunspellAllocator.h from third-party code.
-        "-Wno-undefined-var-template",
-    ]

extensions/spellcheck/hunspell/glue/mozHunspell.cpp

@@ -101,10 +101,6 @@ NS_IMPL_COMPONENT_FACTORY(mozHunspell) {
   return nullptr;
 }
 
-template <>
-mozilla::CountingAllocatorBase<HunspellAllocator>::AmountType
-    mozilla::CountingAllocatorBase<HunspellAllocator>::sAmount(0);
-
 mozHunspell::mozHunspell() {
 #ifdef DEBUG
   // There must be only one instance of this class: it reports memory based on

gfx/thebes/gfxAndroidPlatform.cpp

@@ -70,10 +70,6 @@ class FreetypeReporter final : public nsIMemoryReporter,
 
 NS_IMPL_ISUPPORTS(FreetypeReporter, nsIMemoryReporter)
 
-template <>
-CountingAllocatorBase<FreetypeReporter>::AmountType
-    CountingAllocatorBase<FreetypeReporter>::sAmount(0);
-
 static FT_MemoryRec_ sFreetypeMemoryRecord;
 
 gfxAndroidPlatform::gfxAndroidPlatform() {

xpcom/base/CountingAllocatorBase.h

@@ -147,7 +147,7 @@ class CountingAllocatorBase {
   // must be thread-safe. It may be written during GC, so accesses are not
   // recorded.
   typedef Atomic<size_t, SequentiallyConsistent> AmountType;
-  static AmountType sAmount;
+  static inline AmountType sAmount{0};
 
   MOZ_DEFINE_MALLOC_SIZE_OF_ON_ALLOC(MallocSizeOfOnAlloc)
   MOZ_DEFINE_MALLOC_SIZE_OF_ON_FREE(MallocSizeOfOnFree)

xpcom/build/XPCOMInit.cpp

@@ -190,10 +190,6 @@ class ICUReporter final : public nsIMemoryReporter,
 
 NS_IMPL_ISUPPORTS(ICUReporter, nsIMemoryReporter)
 
-/* static */ template <>
-mozilla::CountingAllocatorBase<ICUReporter>::AmountType
-    mozilla::CountingAllocatorBase<ICUReporter>::sAmount(0);
-
 class OggReporter final : public nsIMemoryReporter,
                           public mozilla::CountingAllocatorBase<OggReporter> {
  public:
@@ -216,10 +212,6 @@ class OggReporter final : public nsIMemoryReporter,
 
 NS_IMPL_ISUPPORTS(OggReporter, nsIMemoryReporter)
 
-/* static */ template <>
-mozilla::CountingAllocatorBase<OggReporter>::AmountType
-    mozilla::CountingAllocatorBase<OggReporter>::sAmount(0);
-
 static bool sInitializedJS = false;
 
 static void InitializeJS() {