From a0cf20ad9171bd0670d81ac842f10064eb7f71c0 Mon Sep 17 00:00:00 2001
From: Dimitry Andric <dim@FreeBSD.org>
Date: Fri, 26 Jan 2024 16:02:51 +0100
Subject: [PATCH] libc++: use build defines and flags similar to upstream.

---
 lib/libc++/Makefile | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/lib/libc++/Makefile b/lib/libc++/Makefile
index a0fe979623b17a..ea93913e358579 100644
--- a/lib/libc++/Makefile
+++ b/lib/libc++/Makefile
@@ -88,16 +88,21 @@ cxxrt_${_S}: ${_LIBCXXRTDIR}/${_S} .NOMETA
 .endfor
 
 WARNS?=		0
+CFLAGS+=	-isystem ${SRCDIR}
 CFLAGS+=	-isystem ${.CURDIR}
 CFLAGS+=	-isystem ${HDRDIR}
-CFLAGS+=	-isystem ${SRCDIR}
 CFLAGS+=	-isystem ${_LIBCXXRTDIR}
 CFLAGS+=	-nostdinc++
 CFLAGS+=	-nostdlib
 CFLAGS+=	-D_LIBCPP_BUILDING_LIBRARY
+CFLAGS+=	-D_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+CFLAGS+=	-D_LIBCPP_REMOVE_TRANSITIVE_INCLUDES
 CFLAGS+=	-DLIBCXXRT
-CFLAGS+=	-ffunction-sections
 CFLAGS+=	-fdata-sections
+CFLAGS+=	-ffunction-sections
+CFLAGS+=	-fno-semantic-interposition
+CFLAGS+=	-fvisibility-inlines-hidden
+CFLAGS+=	-fvisibility=hidden
 CXXSTD?=	c++20
 
 LIBADD+=	cxxrt