[libc] Fix internal alignment in allcoator (#146738)

Summary:
The allocator interface is supposed to have 16 byte alignment (to keep
it consistent with the CPU allocator. We could probably drop this to 8
if desires.) But this was not enforced because the number of bytes used
for the bitfield sometimes resulted in alignment of 8 instead of 16.
Explicitly align the number of bytes to be a multiple of 16 even if
unused.

1 files changed, 2 insertions, 2 deletions

diff --git a/libc/test/integration/src/stdlib/gpu/aligned_alloc.cpp b/libc/test/integration/src/stdlib/gpu/aligned_alloc.cpp
index b966e6953cc2..6e00eb86c680 100644
--- a/libc/test/integration/src/stdlib/gpu/aligned_alloc.cpp
+++ b/libc/test/integration/src/stdlib/gpu/aligned_alloc.cpp
@@ -10,7 +10,7 @@ TEST_MAIN(int, char **, char **) {
   // aligned_alloc with valid alignment and size
   void *ptr = LIBC_NAMESPACE::aligned_alloc(32, 16);
   EXPECT_NE(ptr, nullptr);
-  EXPECT_EQ(__builtin_is_aligned(ptr, 32), 0U);
+  EXPECT_TRUE(__builtin_is_aligned(ptr, 32));
 
   LIBC_NAMESPACE::free(ptr);
 
@@ -23,7 +23,7 @@ TEST_MAIN(int, char **, char **) {
   void *div =
       LIBC_NAMESPACE::aligned_alloc(alignment, (gpu::get_thread_id() + 1) * 4);
   EXPECT_NE(div, nullptr);
-  EXPECT_EQ(__builtin_is_aligned(div, alignment), 0U);
+  EXPECT_TRUE(__builtin_is_aligned(div, alignment));
 
   return 0;
 }