Roll libc++ from 0e3285ac398e to 4cba0fa3571b (1 revision)

https://chromium.googlesource.com/external/github.com/llvm/llvm-project/libcxx.git/+log/0e3285ac398e..4cba0fa3571b

2025-11-14 [email protected] [libc++][hardening] Allow setting the assertion semantic via CMake. (#167636)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/libcxx-chromium
Please CC [email protected],[email protected] on the revert to ensure that a human
is aware of the problem.

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To report a problem with the AutoRoller itself, please file a bug:
https://issues.skia.org/issues/new?component=1389291&template=1850622

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Change-Id: Iba577893c0e246990919ff5f5e954419f6c386cb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7157574
Commit-Queue: Nico Weber <[email protected]>
Reviewed-by: Hans Wennborg <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1548042}
NOKEYCHECK=True
GitOrigin-RevId: 88e128a3b4d0f4c0107de549e55fb182bd8ce023

Author: nico

deps_revisions.gni

@@ -5,5 +5,5 @@
 declare_args() {
   # Used to cause full rebuilds on libc++ rolls. This should be kept in sync
   # with the libcxx_revision var in //DEPS.
-  libcxx_revision = "0e3285ac398e8769e3496d077ecfe10d51cd3c53"
+  libcxx_revision = "4cba0fa3571b78aca49da1e4e51bfd63a43729ee"
 }

third_party/libc++/__config_site

@@ -63,6 +63,15 @@
 #define _LIBCPP_PSTL_BACKEND_STD_THREAD
 #endif
 
+// _LIBCPP_HARDENING_MODE_DEFAULT is not defined here. Instead, we define
+// _LIBCPP_HARDENING_MODE in build/config/compiler/BUILD.gn.
+
+// Define _LIBCPP_ASSERTION_SEMANTIC_DEFAULT instead of
+// _LIBCPP_ASSERTION_SEMANTIC because the latter requires setting
+// _LIBCPP_HAS_EXPERIMENTAL_LIBRARY too.
+#define _LIBCPP_ASSERTION_SEMANTIC_DEFAULT \
+    _LIBCPP_ASSERTION_SEMANTIC_HARDENING_DEPENDENT
+
 // Settings below aren't part of __config_site upstream.
 // We set them here since we want them to take effect everywhere,
 // unconditionally.

third_party/libc++/libcxx_headers.gni

@@ -11,7 +11,7 @@
 import("//buildtools/deps_revisions.gni")
 
 assert(
-    libcxx_revision == "0e3285ac398e8769e3496d077ecfe10d51cd3c53",
+    libcxx_revision == "4cba0fa3571b78aca49da1e4e51bfd63a43729ee",
     "libcxx_headers.gni and third_party/libc++ are out of sync.$0x0A$0x0AIf you were messing around with the libc++ repository, run:$0x0A`buildtools/third_party/libc++/generate_libcxx_headers.py`$0x0A$0x0AIf the script doesn't resolve the error, file a bug to msta@ with reproduction details.$0x0A")
 
 libcxx_headers = [