[gcc r13-8138] libstdc++: Use <cstdint> instead of <stdint.h> in <bits/atomic_wait.h>

[Jonathan Wakely <redi@gcc.gnu.org>]

https://gcc.gnu.org/g:d62feab6aa7d023f7ba916f1618b8a6137ac5659

commit r13-8138-gd62feab6aa7d023f7ba916f1618b8a6137ac5659
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Thu Dec 7 11:00:02 2023 +0000

    libstdc++: Use <cstdint> instead of <stdint.h> in <bits/atomic_wait.h>
    
    In r14-5922-g6c8f2d3a08bc01 I added <stdint.h> to <bits/atomic_wait.h>,
    so that uintptr_t is declared if that header is compiled as a header
    unit. I used <stdint.h> because that's what <atomic> already includes,
    so it seemed simpler to be consistent. However, this means that name
    lookup for uintptr_t in <bits/atomic_wait.h> depends on whether
    <cstdint> has been included by another header first. Whether name lookup
    finds std::uintptr_t or ::uintptr_t will depend on include order. This
    causes problems when compiling modules with Clang:
    
    bits/atomic_wait.h:251:7: error: 'std::__detail::__waiter_pool_base' has different definitions in different modules; first difference is defined here found method '_S_for' with body
          _S_for(const void* __addr) noexcept
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    bits/atomic_wait.h:251:7: note: but in 'tm.<global>' found method '_S_for' with different body
          _S_for(const void* __addr) noexcept
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    
    By including <cstdint> we would ensure that name lookup always finds the
    name in namespace std. Alternatively, we can stop including <stdint.h>
    for those types, so that we don't declare the entire contents of
    <stdint.h> when we only need a couple of types from it. This patch does
    the former, which is appropriate for backporting.
    
    libstdc++-v3/ChangeLog:
    
            * include/bits/atomic_wait.h: Include <cstdint> instead of
            <stdint.h>.
    
    (cherry picked from commit 2f512f6fcdd55296daff3e01a250d866491014e6)

Diff:
---
 libstdc++-v3/include/bits/atomic_wait.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libstdc++-v3/include/bits/atomic_wait.h b/libstdc++-v3/include/bits/atomic_wait.h
index aaf36832ea3..fc840578c22 100644
--- a/libstdc++-v3/include/bits/atomic_wait.h
+++ b/libstdc++-v3/include/bits/atomic_wait.h
@@ -34,7 +34,7 @@
 
 #include <bits/c++config.h>
 #if defined _GLIBCXX_HAS_GTHREADS || defined _GLIBCXX_HAVE_LINUX_FUTEX
-#include <stdint.h>
+#include <cstdint>
 #include <bits/functional_hash.h>
 #include <bits/gthr.h>
 #include <ext/numeric_traits.h>