diff --git a/external/apache2/llvm/librt/Makefile.inc b/external/apache2/llvm/librt/Makefile.inc
index fc66467f3a86..cf9f25d32e05 100644
--- a/external/apache2/llvm/librt/Makefile.inc
+++ b/external/apache2/llvm/librt/Makefile.inc
@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile.inc,v 1.4 2021/05/30 01:56:58 joerg Exp $
+#	$NetBSD: Makefile.inc,v 1.5 2023/08/08 06:27:31 mrg Exp $
 
 LLVM_TOPLEVEL:=	${.PARSEDIR}/..
 NOSTATICLIB=	yes
@@ -10,3 +10,5 @@ CWARNFLAGS.gcc+=	${${HAVE_GCC:U0} >= 9:? -Wno-error=init-list-lifetime :}
 
 LLVM_INCLUDE_OBJDIR!=	cd ${LLVM_TOPLEVEL}/include && ${PRINTOBJDIR}
 LLVM_MODULE_CACHE=	${LLVM_INCLUDE_OBJDIR}/module.cache-rt
+
+CXXFLAGS+=		${CC_WNO_MISSING_TEMPLATE_KEYWORD}
diff --git a/external/bsd/file/lib/Makefile b/external/bsd/file/lib/Makefile
index d903b157b317..5194bc530194 100644
--- a/external/bsd/file/lib/Makefile
+++ b/external/bsd/file/lib/Makefile
@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.16 2023/06/03 21:31:45 lukem Exp $
+#	$NetBSD: Makefile,v 1.17 2023/08/08 06:27:31 mrg Exp $
 #
 
 USE_FORT?= yes	# data driven bugs?
@@ -35,7 +35,8 @@ MLINKS+=	libmagic.3 magic_open.3 \
 INCS=		magic.h
 INCSDIR=	/usr/include
 
-COPTS.softmagic.c = -Wno-format-nonliteral
+COPTS.softmagic.c+=	-Wno-format-nonliteral
+COPTS.readelf.c+=	${CC_WNO_MAYBE_UNINITIALIZED}
 
 magic.c:	magic.h
 magic.h:        magic.h.in
diff --git a/external/gpl3/gcc/README.warnings b/external/gpl3/gcc/README.warnings
index 10c203da9360..ae7eac61435a 100644
--- a/external/gpl3/gcc/README.warnings
+++ b/external/gpl3/gcc/README.warnings
@@ -1,4 +1,4 @@
-$NetBSD: README.warnings,v 1.3 2023/06/03 09:09:07 lukem Exp $
+$NetBSD: README.warnings,v 1.4 2023/08/08 06:27:33 mrg Exp $
 
 What to do about GCC warnings and NetBSD.
 
@@ -22,8 +22,47 @@ modified for updates to warnings and new warnings.
    COPTS.foo.c += ${CC_WNO_ADDRESS_OF_PACKED_MEMBER}
    COPTS.foo.c += ${CC_WNO_MAYBE_UNINITIALIZED}
    COPTS.foo.c += ${CC_WNO_RETURN_LOCAL_ADDR}
+   COPTS.foo.c += ${CC_WNO_MISSING_TEMPLATE_KEYWORD}
+   COPTS.foo.c += ${CC_WNO_STRINGOP_OVERREAD}
+   COPTS.foo.c += ${CC_WNO_REGISTER}
+   COPTS.foo.c += ${CC_WNO_ARRAY_BOUNDS}
 
 
+new GCC 12 warnings:
+
+  -Wno-missing-template-keyword
+
+      This warning trips on older C++ code, and should only be applyed to 3rd
+      party code.
+
+      bsd.own.mk variable: ${CC_WNO_MISSING_TEMPLATE_KEYWORD}
+     
+  -Wno-stringop-overread
+
+      This warning triggers when array bounds appear to be exceeded.  There
+      maybe some bugs related to this warning in GCC 12.
+
+      bsd.own.mk variable: ${CC_WNO_STRINGOP_OVERREAD}
+     
+  -Wno-register
+
+      This warning triggers in C++17 mode where 'register' has been removed,
+      and should only be applied to 3rd party code.
+
+      bsd.own.mk variable: ${CC_WNO_REGISTER}
+     
+  -Wno-array-bounds
+
+      This warning triggers with a number of code issues that tend to be real
+      problem but require careful adjustments to fix properly, when there are
+      platform related accesses beyond the immediately size and address of
+      known variables (real bugs to fix), but also may trigger when passing
+      C arrays vs C pointers to functions, often incorrectly.  See
+	https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110878
+
+      bsd.own.mk variable: ${CC_WNO_ARRAY_BOUNDS}
+     
+
 new GCC 10 warnings:
 
   GCC 10 switched the default from "-fcommon" to "-fno-common",
diff --git a/external/mit/xorg/lib/dri.old/Makefile b/external/mit/xorg/lib/dri.old/Makefile
index effcbfaf6570..7cb496a529c6 100644
--- a/external/mit/xorg/lib/dri.old/Makefile
+++ b/external/mit/xorg/lib/dri.old/Makefile
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.7 2023/07/15 21:24:46 rjs Exp $
+# $NetBSD: Makefile,v 1.8 2023/08/08 06:27:31 mrg Exp $
 
 # Link the mesa_dri_drivers mega driver.
 
@@ -511,6 +511,9 @@ COPTS.brw_fs_copy_propagation.cpp+=	-Wno-error=stack-protector
 COPTS.brw_fs.cpp+=	-Wno-error=stack-protector
 COPTS.brw_fs_reg_allocate.cpp+=	-Wno-error=stack-protector
 
+COPTS.prog_opt_constant_fold.c+=	${CC_WNO_STRINGOP_OVERREAD}
+COPTS.s_texfilter.c+=			${CC_WNO_STRINGOP_OVERREAD}
+
 .include <bsd.lib.mk>
 .else
 .include <bsd.inc.mk>
diff --git a/external/mit/xorg/lib/gallium.old/Makefile b/external/mit/xorg/lib/gallium.old/Makefile
index 3fec2a60682f..55b2fe3d1c1a 100644
--- a/external/mit/xorg/lib/gallium.old/Makefile
+++ b/external/mit/xorg/lib/gallium.old/Makefile
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.6 2023/07/15 21:24:46 rjs Exp $
+# $NetBSD: Makefile,v 1.7 2023/08/08 06:27:31 mrg Exp $
 
 # Transparent struct/union broken
 NOLINT=yes
@@ -1215,8 +1215,17 @@ COPTS+=	${${ACTIVE_CC} == "clang":? -Wa,-Av8plus  :}
 COPTS.nir.c += -O1
 .endif
 
+# XXXGCC12
+.if ${MACHINE_ARCH} == "m68k"
+COPTS.st_glsl_to_tgsi.cpp += -O1
+COPTS.vl_bicubic_filter.c += -O1
+COPTS.nir_opt_algebraic.c += -Os -fno-jump-tables
+.endif
+
 COPTS.u_atomic.c+=	${${ACTIVE_CC} == "gcc" && ${HAVE_GCC:U0} >= 10:? -Wno-builtin-declaration-mismatch :}
 
+COPTS.prog_opt_constant_fold.c+=	${CC_WNO_STRINGOP_OVERREAD}
+
 .include <bsd.lib.mk>
 # Don't regenerate c files
 .y.c:
diff --git a/external/mit/xorg/lib/libGLU/Makefile b/external/mit/xorg/lib/libGLU/Makefile
index e7a7571e1490..6ac47363df0c 100644
--- a/external/mit/xorg/lib/libGLU/Makefile
+++ b/external/mit/xorg/lib/libGLU/Makefile
@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.22 2021/08/24 03:10:11 mrg Exp $
+#	$NetBSD: Makefile,v 1.23 2023/08/08 06:27:31 mrg Exp $
 
 .include <bsd.own.mk>
 
@@ -155,5 +155,8 @@ COPTS.arcsorter.cc+=	-Wno-error
 COPTS.sorter.cc+=	-Wno-error
 COPTS.tobezier.cc+=	-Wno-error
 
+COPTS.varray.cc+=	${CC_WNO_REGISTER}
+COPTS.project.c+=	${CC_WNO_STRINGOP_OVERFLOW}
+
 CWARNFLAGS.clang+=	-Wno-parentheses -Wno-tautological-compare
 CWARNFLAGS.clang+=	-Wno-deprecated-register
diff --git a/external/public-domain/sqlite/lib/Makefile b/external/public-domain/sqlite/lib/Makefile
index 4273bee7c5e1..145df7a070e2 100644
--- a/external/public-domain/sqlite/lib/Makefile
+++ b/external/public-domain/sqlite/lib/Makefile
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.15 2023/06/03 09:09:08 lukem Exp $
+# $NetBSD: Makefile,v 1.16 2023/08/08 06:27:32 mrg Exp $
 
 LIB=		sqlite3
 INCS=		sqlite3.h sqlite3ext.h
@@ -20,7 +20,11 @@ FILESDIR_sqlite3.pc=	/usr/lib/pkgconfig
 CLEANFILES+=sqlite3.pc
 
 CWARNFLAGS.clang+=	-Wno-error=implicit-int-float-conversion
-COPTS.sqlite3.c+=	${CC_WNO_RETURN_LOCAL_ADDR}
+
+COPTS.sqlite3.c+=	${CC_WNO_RETURN_LOCAL_ADDR} ${CC_WNO_STRINGOP_OVERFLOW}
+COPTS.sqlite3.c+=	${CC_WNO_ARRAY_BOUNDS}
+COPTS.sqlite3.c+=	-Wno-error=misleading-indentation
+COPTS.sqlite3.c+=	-Wno-error=restrict
 
 .include <bsd.own.mk>
 
diff --git a/share/mk/bsd.own.mk b/share/mk/bsd.own.mk
index 911314e44b97..35bf2297f9e5 100644
--- a/share/mk/bsd.own.mk
+++ b/share/mk/bsd.own.mk
@@ -1,4 +1,4 @@
-#	$NetBSD: bsd.own.mk,v 1.1351 2023/08/08 03:44:12 mrg Exp $
+#	$NetBSD: bsd.own.mk,v 1.1352 2023/08/08 06:27:32 mrg Exp $
 
 # This needs to be before bsd.init.mk
 .if defined(BSD_MK_COMPAT_FILE)
@@ -700,6 +700,10 @@ CC_WNO_MAYBE_UNINITIALIZED=	${${ACTIVE_CC} == "gcc" && ${HAVE_GCC:U0} >= 10:? -W
 CC_WNO_RETURN_LOCAL_ADDR=	${${ACTIVE_CC} == "gcc" && ${HAVE_GCC:U0} >= 10:? -Wno-return-local-addr :}
 CC_WNO_STRINGOP_OVERFLOW=	${${ACTIVE_CC} == "gcc" && ${HAVE_GCC:U0} >= 7:? -Wno-stringop-overflow :}
 CC_WNO_STRINGOP_TRUNCATION=	${${ACTIVE_CC} == "gcc" && ${HAVE_GCC:U0} >= 8:? -Wno-stringop-truncation :}
+CC_WNO_MISSING_TEMPLATE_KEYWORD=${${ACTIVE_CC} == "gcc" && ${HAVE_GCC:U0} >= 12:? -Wno-missing-template-keyword :}
+CC_WNO_STRINGOP_OVERREAD=	${${ACTIVE_CC} == "gcc" && ${HAVE_GCC:U0} >= 12:? -Wno-stringop-overread :}
+CC_WNO_REGISTER=		${${ACTIVE_CC} == "gcc" && ${HAVE_GCC:U0} >= 12:? -Wno-register :}
+CC_WNO_ARRAY_BOUNDS=		${${ACTIVE_CC} == "gcc" && ${HAVE_GCC:U0} >= 12:? -Wno-array-bounds :}
 
 # For each ${MACHINE_CPU}, list the ports that use it.
 MACHINES.aarch64=	evbarm
diff --git a/sys/arch/hppa/conf/Makefile.hppa b/sys/arch/hppa/conf/Makefile.hppa
index ef758ce1455f..3c9c87f20d14 100644
--- a/sys/arch/hppa/conf/Makefile.hppa
+++ b/sys/arch/hppa/conf/Makefile.hppa
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile.hppa,v 1.8 2020/09/14 16:13:18 skrll Exp $
+# $NetBSD: Makefile.hppa,v 1.9 2023/08/08 06:27:32 mrg Exp $
 
 # Makefile for NetBSD
 #
@@ -87,6 +87,9 @@ com_gsc.o clock.o pdc.o autoconf.o machdep.o: Makefile
 ## (7) misc settings
 ##
 
+# GCC 12 gets this wrong
+COPTS.pdc.c+=	${CC_WNO_ARRAY_BOUNDS}
+
 ##
 ## (8) config(8) generated machinery
 ##
diff --git a/sys/conf/copts.mk b/sys/conf/copts.mk
index 0a8fa4b22a63..a904520b7791 100644
--- a/sys/conf/copts.mk
+++ b/sys/conf/copts.mk
@@ -1,4 +1,4 @@
-#	$NetBSD: copts.mk,v 1.10 2023/06/03 21:30:21 lukem Exp $
+#	$NetBSD: copts.mk,v 1.11 2023/08/08 06:27:32 mrg Exp $
 
 # MI per-file compiler options required.
 
@@ -29,4 +29,21 @@ COPTS.in6_pcb.c+=	${CC_WNO_RETURN_LOCAL_ADDR}
 COPTS.magma.c+=		${CC_WNO_MAYBE_UNINITIALIZED}
 .endif
 
+# Some of these indicate a potential GCC bug:
+#   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110878
+.if defined(HAVE_GCC) && ${HAVE_GCC} >= 12 && ${ACTIVE_CC} == "gcc" && \
+    (${MACHINE_ARCH} == "aarch64" || ${MACHINE_ARCH} == "aarch64eb")
+COPTS.aes_armv8.c+=	${CC_WNO_STRINGOP_OVERREAD} ${CC_WNO_STRINGOP_OVERFLOW}
+COPTS.aes_neon.c+=	${CC_WNO_STRINGOP_OVERREAD} ${CC_WNO_STRINGOP_OVERFLOW} -flax-vector-conversions
+COPTS.aes_neon_subr.c+=	${CC_WNO_ARRAY_BOUNDS} -flax-vector-conversions
+COPTS.chacha_neon.c+=	-flax-vector-conversions
+.endif
+
+.if ${MACHINE_ARCH} == "x86_64" || ${MACHINE_ARCH} == "i386"
+COPTS.aes_ni.c+=	${CC_WNO_STRINGOP_OVERREAD} ${CC_WNO_STRINGOP_OVERFLOW}
+COPTS.aes_sse2_subr.c+=	${CC_WNO_ARRAY_BOUNDS}
+COPTS.aes_ssse3_subr.c+=${CC_WNO_ARRAY_BOUNDS}
+COPTS.aes_via.c+=	${CC_WNO_ARRAY_BOUNDS}
+.endif
+
 .endif
diff --git a/tests/lib/libc/string/Makefile b/tests/lib/libc/string/Makefile
index 12ea5c1dfb0d..127850b198dd 100644
--- a/tests/lib/libc/string/Makefile
+++ b/tests/lib/libc/string/Makefile
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.14 2023/06/03 09:09:15 lukem Exp $
+# $NetBSD: Makefile,v 1.15 2023/08/08 06:27:32 mrg Exp $
 
 .include <bsd.own.mk>
 
@@ -30,4 +30,7 @@ TESTS_C+=	t_swab
 
 WARNS=		4
 
+# Explicitly tries to test this case
+COPTS.t_strlen.c+=	${CC_WNO_STRINGOP_OVERREAD}
+
 .include <bsd.test.mk>
diff --git a/tests/lib/libc/sys/Makefile b/tests/lib/libc/sys/Makefile
index 181026a01b99..21e66aa74946 100644
--- a/tests/lib/libc/sys/Makefile
+++ b/tests/lib/libc/sys/Makefile
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.73 2023/06/03 08:52:59 lukem Exp $
+# $NetBSD: Makefile,v 1.74 2023/08/08 06:27:32 mrg Exp $
 
 MKMAN=	no
 
@@ -156,4 +156,7 @@ WARNS=			4
 CWARNFLAGS.gcc+=	${CC_WNO_ADDRESS_OF_PACKED_MEMBER} \
 			${${ACTIVE_CC} == "gcc" && ${HAVE_GCC:U0} >= 8:? -Wno-error=deprecated :}
 
+# Explicitly breaks this
+COPTS.t_wait.c+=	${CC_WNO_ARRAY_BOUNDS} ${CC_WNO_STRINGOP_OVERFLOW}
+
 .include <bsd.test.mk>
diff --git a/tests/sys/crypto/aes/Makefile b/tests/sys/crypto/aes/Makefile
index 054933d887fc..fe569c19684d 100644
--- a/tests/sys/crypto/aes/Makefile
+++ b/tests/sys/crypto/aes/Makefile
@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.6 2020/09/08 17:35:27 jakllsch Exp $
+#	$NetBSD: Makefile,v 1.7 2023/08/08 06:27:32 mrg Exp $
 
 .include <bsd.own.mk>
 
@@ -80,4 +80,15 @@ SRCS.t_aes+=	aes_via.c
 
 WARNS=		5
 
+# Many of these are probably GCC bugs, see
+#   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110878
+COPTS.aes_armv8.c+=	${CC_WNO_STRINGOP_OVERREAD} ${CC_WNO_STRINGOP_OVERFLOW}
+COPTS.aes_bear.c+=	${CC_WNO_STRINGOP_OVERFLOW} ${CC_WNO_ARRAY_BOUNDS}
+COPTS.aes_neon_subr.c+=	${CC_WNO_ARRAY_BOUNDS}
+
+COPTS.aes_ni.c+=	${CC_WNO_STRINGOP_OVERREAD} ${CC_WNO_STRINGOP_OVERFLOW}
+COPTS.aes_sse2_subr.c+=	${CC_WNO_ARRAY_BOUNDS}
+COPTS.aes_ssse3_subr.c+=${CC_WNO_ARRAY_BOUNDS}
+COPTS.aes_via.c+=	${CC_WNO_ARRAY_BOUNDS}
+
 .include <bsd.test.mk>
diff --git a/usr.bin/pkill/Makefile b/usr.bin/pkill/Makefile
index e91803324df6..82c5cecc3f5e 100644
--- a/usr.bin/pkill/Makefile
+++ b/usr.bin/pkill/Makefile
@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.4 2010/12/06 21:16:54 mrg Exp $
+#	$NetBSD: Makefile,v 1.5 2023/08/08 06:27:32 mrg Exp $
 
 PROG=	pkill
 
@@ -10,4 +10,6 @@ LINKS+=	${BINDIR}/pkill ${BINDIR}/prenice
 MLINKS+=pkill.1 pgrep.1
 MLINKS+=pkill.1 prenice.1
 
+COPTS.pkill.c+=		${CC_WNO_STRINGOP_OVERFLOW}
+
 .include <bsd.prog.mk>
diff --git a/usr.sbin/mrouted/Makefile b/usr.sbin/mrouted/Makefile
index 1a4192e29ae2..f399cc16270c 100644
--- a/usr.sbin/mrouted/Makefile
+++ b/usr.sbin/mrouted/Makefile
@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.19 2023/06/03 09:09:22 lukem Exp $
+#	$NetBSD: Makefile,v 1.20 2023/08/08 06:27:33 mrg Exp $
 #	from: Id: Makefile,v 1.5 1993/06/24 05:11:16 deering Exp
 
 .include <bsd.own.mk>
@@ -19,5 +19,6 @@ CWARNFLAGS.gcc+=        ${CC_WNO_ADDRESS_OF_PACKED_MEMBER}
 
 COPTS.cfparse.c+=	${CC_WNO_STRINGOP_TRUNCATION}
 COPTS.vif.c+=		${CC_WNO_STRINGOP_TRUNCATION}
+COPTS.route.c+=		${CC_WNO_ARRAY_BOUNDS}
 
 .include <bsd.prog.mk>
diff --git a/usr.sbin/traceroute/Makefile b/usr.sbin/traceroute/Makefile
index 1ae6cb81073a..94e7190a55e6 100644
--- a/usr.sbin/traceroute/Makefile
+++ b/usr.sbin/traceroute/Makefile
@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.22 2021/02/03 06:49:18 roy Exp $	
+#	$NetBSD: Makefile,v 1.23 2023/08/08 06:27:33 mrg Exp $	
 
 USE_FORT?= yes	# network client
 
@@ -30,4 +30,6 @@ SANITIZER_RENAME_SYMBOL.rump+=	getifaddrs
 
 AWKS=	median.awk mean.awk 
 
+COPTS.traceroute.c+=	${CC_WNO_ARRAY_BOUNDS}
+
 .include <bsd.prog.mk>