www/chromium: unbreak on i386 by enforcing 8 byte alignment on i386 in partition alloc

www/chromium/Makefile

@@ -15,7 +15,6 @@ LICENSE=	BSD3CLAUSE LGPL21 MPL11
 LICENSE_COMB=	multi
 
 ONLY_FOR_ARCHS=	aarch64 amd64 i386
-BROKEN_i386=	does not build due to 4k alignment
 
 BUILD_DEPENDS=	bash:shells/bash \
 		${PYTHON_PKGNAMEPREFIX}Jinja2>0:devel/py-Jinja2@${PY_FLAVOR} \

www/chromium/files/patch-base_allocator_partition__allocator_partition__alloc.cc

@@ -1,16 +0,0 @@
---- base/allocator/partition_allocator/partition_alloc.cc.orig	2022-10-24 13:33:33 UTC
-+++ base/allocator/partition_allocator/partition_alloc.cc
-@@ -67,8 +67,13 @@ void PartitionAllocGlobalInit(OomFunction on_out_of_me
-       "maximum direct mapped allocation");
- 
-   // Check that some of our zanier calculations worked out as expected.
-+#if defined(__i386__) && defined(OS_FREEBSD)
-+  static_assert(internal::kSmallestBucket >= internal::kAlignment,
-+                "generic smallest bucket");
-+#else
-   static_assert(internal::kSmallestBucket == internal::kAlignment,
-                 "generic smallest bucket");
-+#endif
-   static_assert(internal::kMaxBucketed == 983040, "generic max bucketed");
-   STATIC_ASSERT_OR_PA_CHECK(
-       internal::MaxSystemPagesPerRegularSlotSpan() <= 16,

www/chromium/files/patch-base_allocator_partition__allocator_partition__alloc__forward.h

@@ -0,0 +1,16 @@
+--- base/allocator/partition_allocator/partition_alloc_forward.h.orig	2022-11-06 16:08:29 UTC
++++ base/allocator/partition_allocator/partition_alloc_forward.h
+@@ -25,9 +25,13 @@ namespace internal {
+ // the second one 16. We could technically return something different for
+ // malloc() and operator new(), but this would complicate things, and most of
+ // our allocations are presumably coming from operator new() anyway.
++#if defined(__i386__) && defined(OS_FREEBSD)
++constexpr size_t kAlignment = 8;
++#else
+ constexpr size_t kAlignment =
+     std::max(alignof(max_align_t),
+              static_cast<size_t>(__STDCPP_DEFAULT_NEW_ALIGNMENT__));
++#endif
+ static_assert(kAlignment <= 16,
+               "PartitionAlloc doesn't support a fundamental alignment larger "
+               "than 16 bytes.");

www/chromium/files/patch-base_allocator_partition__allocator_partition__page.h

@@ -1,14 +1,6 @@
---- base/allocator/partition_allocator/partition_page.h.orig	2022-10-24 13:33:33 UTC
+--- base/allocator/partition_allocator/partition_page.h.orig	2022-11-06 16:08:29 UTC
 +++ base/allocator/partition_allocator/partition_page.h
-@@ -138,13 +138,14 @@ struct SlotSpanMetadata {
+@@ -144,7 +144,7 @@ struct SlotSpanMetadata {
-   PartitionBucket<thread_safe>* const bucket = nullptr;
- 
-   // CHECK()ed in AllocNewSlotSpan().
--#if defined(PA_HAS_64_BITS_POINTERS) && BUILDFLAG(IS_APPLE)
-+#if (defined(PA_HAS_64_BITS_POINTERS) && BUILDFLAG(IS_APPLE)) || \
-+    (BUILDFLAG(IS_FREEBSD) && defined(__i386__))
-   // System page size is not a constant on Apple OSes, but is either 4 or 16kiB
-   // (1 << 12 or 1 << 14), as checked in PartitionRoot::Init(). And
    // PartitionPageSize() is 4 times the OS page size.
    static constexpr size_t kMaxSlotsPerSlotSpan =
        4 * (1 << 14) / kSmallestBucket;
@@ -17,13 +9,3 @@
    // System page size can be 4, 16, or 64 kiB on Linux on arm64. 64 kiB is
    // currently (kMaxSlotsPerSlotSpanBits == 13) not supported by the code,
    // so we use the 16 kiB maximum (64 kiB will crash).
-@@ -158,7 +159,9 @@ struct SlotSpanMetadata {
- #endif  // defined(PA_HAS_64_BITS_POINTERS) && BUILDFLAG(IS_APPLE)
-   // The maximum number of bits needed to cover all currently supported OSes.
-   static constexpr size_t kMaxSlotsPerSlotSpanBits = 13;
-+#if !BUILDFLAG(IS_FREEBSD) && defined(__i386__)
-   static_assert(kMaxSlotsPerSlotSpan < (1 << kMaxSlotsPerSlotSpanBits), "");
-+#endif
- 
-   // |marked_full| isn't equivalent to being full. Slot span is marked as full
-   // iff it isn't on the active slot span list (or any other list).