diff --git a/lib/libc/Makefile b/lib/libc/Makefile
--- a/lib/libc/Makefile
+++ b/lib/libc/Makefile
@@ -62,6 +62,10 @@
 #
 LDFLAGS+= -nodefaultlibs
 LIBADD+=	compiler_rt
+LIBADD+=	sys
+.if defined(COMPAT_libcompat)
+LDFLAGS+=	-Wl,--rpath=/usr/lib${COMPAT_libcompat}
+.endif
 
 LDFLAGS+=-Wl,--auxiliary,libsys.so.7
 
diff --git a/lib/libc/tests/ssp/Makefile b/lib/libc/tests/ssp/Makefile
--- a/lib/libc/tests/ssp/Makefile
+++ b/lib/libc/tests/ssp/Makefile
@@ -10,6 +10,7 @@
 # override the sanitizer runtime libraries to be the ones installed on the
 # target system.
 CFLAGS.h_raw+=	-fsanitize=bounds
+LIBADD+=sys
 .elif ${COMPILER_TYPE} == "gcc"
 CFLAGS.h_raw+=	--param ssp-buffer-size=1
 LDADD+=	-lssp
diff --git a/lib/libsys/Makefile b/lib/libsys/Makefile
--- a/lib/libsys/Makefile
+++ b/lib/libsys/Makefile
@@ -57,6 +57,9 @@
 MIASM=
 NOASM=
 
+SYM_MAPS+=	${LIBSYS_SRCTOP}/Symbol.map
+SRCS+=	auxv.c
+
 .include "${LIBSYS_SRCTOP}/Makefile.sys"
 
 SYM_MAPS+=	${LIBSYS_SRCTOP}/Symbol.thr.map
diff --git a/lib/libsys/Makefile.sys b/lib/libsys/Makefile.sys
--- a/lib/libsys/Makefile.sys
+++ b/lib/libsys/Makefile.sys
@@ -47,8 +47,6 @@
 NOASM+=  sched_getcpu.o
 PSEUDO+= _sched_getcpu.o
 
-SRCS+= auxv.c
-
 SRCS+= brk.c
 SRCS+= closefrom.c
 SRCS+= pipe.c
@@ -58,6 +56,14 @@
 
 SRCS+=	compat-stub.c
 
+.if ${LIB} == "c"
+# Trapping stubs in dynamic libc to be filtered by libsys.
+SOBJS+=	libc_stubs.pico
+
+# Link the full implementation of ELF auxargs for static libc.
+STATICOBJS+=	auxv.o
+.endif
+
 INTERPOSED = \
 	accept \
 	accept4 \
diff --git a/lib/libsys/Symbol.map b/lib/libsys/Symbol.map
new file mode 100644
--- /dev/null
+++ b/lib/libsys/Symbol.map
@@ -0,0 +1,5 @@
+FBSDprivate_1.0 {
+	__elf_aux_vector;
+	__init_elf_aux_vector;
+	_elf_aux_info;
+};
diff --git a/lib/libsys/Symbol.sys.map b/lib/libsys/Symbol.sys.map
--- a/lib/libsys/Symbol.sys.map
+++ b/lib/libsys/Symbol.sys.map
@@ -433,12 +433,10 @@
 
 FBSDprivate_1.0 {
 	/* Add entries in sort(1) order */
-	__elf_aux_vector;
 	__libc_sigwait;
 	__libsys_interposing_slot;
 	__set_error_selector;
 	__sigwait;
-	_elf_aux_info;
 	gssd_syscall;
 	nlm_syscall;
 	rpctls_syscall;
diff --git a/lib/libsys/libc_stubs.c b/lib/libsys/libc_stubs.c
new file mode 100644
--- /dev/null
+++ b/lib/libsys/libc_stubs.c
@@ -0,0 +1,11 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2024 SRI International
+ */
+
+#define STUB_FUNC(f)	\
+    void (f)(void);	\
+    void (f)(void) { __builtin_trap(); }
+
+STUB_FUNC(elf_aux_info);
diff --git a/lib/libthr/Makefile b/lib/libthr/Makefile
--- a/lib/libthr/Makefile
+++ b/lib/libthr/Makefile
@@ -7,6 +7,11 @@
 PACKAGE=	clibs
 SHLIBDIR?= /lib
 
+LIBADD=	c sys
+.if defined(COMPAT_libcompat)
+LDFLAGS+=	-Wl,--rpath=/usr/lib${COMPAT_libcompat}
+.endif
+
 .include <src.opts.mk>
 MK_SSP=	no
 
diff --git a/share/mk/bsd.libnames.mk b/share/mk/bsd.libnames.mk
--- a/share/mk/bsd.libnames.mk
+++ b/share/mk/bsd.libnames.mk
@@ -174,7 +174,7 @@
 LIBZPOOL?=	${LIBDESTDIR}${LIBDIR_BASE}/libzpool.a
 LIBZUTIL?=	${LIBDESTDIR}${LIBDIR_BASE}/libzutil.a
 
-# enforce the 2 -lpthread and -lc to always be the last in that exact order
+# enforce -lpthread, -lc, and -lsys to always be the last in that exact order
 .if defined(LDADD)
 .if ${LDADD:M-lpthread}
 LDADD:=	${LDADD:N-lpthread} -lpthread
@@ -182,6 +182,9 @@
 .if ${LDADD:M-lc}
 LDADD:=	${LDADD:N-lc} -lc
 .endif
+.if ${LDADD:M-lsys}
+LDADD:=	${LDADD:N-lsys} -lsys
+.endif
 .endif
 
 # Only do this for src builds.
diff --git a/share/mk/src.libnames.mk b/share/mk/src.libnames.mk
--- a/share/mk/src.libnames.mk
+++ b/share/mk/src.libnames.mk
@@ -394,7 +394,7 @@
 _DP_ztest=	geom m nvpair umem zpool pthread avl zfs_core spl zutil zfs uutil icp
 # The libc dependencies are not strictly needed but are defined to make the
 # assert happy.
-_DP_c=		compiler_rt
+_DP_c=		compiler_rt sys
 # Use libssp_nonshared only on i386 and power*.  Other archs emit direct calls
 # to __stack_chk_fail, not __stack_chk_fail_local provided by libssp_nonshared.
 .if ${MK_SSP} != "no" && \
@@ -410,6 +410,10 @@
     (${MACHINE_ARCH} == "i386" || ${MACHINE_ARCH:Mpower*} != "")
 _DP_sys+=	ssp_nonshared
 .endif
+.if !defined(BOOTSTRAPPING)
+_DP_thr=	c sys
+_DP_pthread=	${_DP_thr}
+.endif
 _DP_tacplus=	md pam
 _DP_ncursesw=	tinfow
 _DP_formw=	ncursesw