Index: devel/valgrind/Makefile
===================================================================
--- devel/valgrind/Makefile	(revision 487542)
+++ devel/valgrind/Makefile	(working copy)
@@ -51,7 +51,8 @@
 		${FILESDIR}/accept4_syscall.patch:-p1 \
 		${FILESDIR}/jail_syscalls.patch:-p1 \
 		${FILESDIR}/kldload_syscalls.patch:-p1 \
-		${FILESDIR}/missing_fcntls.patch:-p1
+		${FILESDIR}/missing_fcntls.patch:-p1 \
+		${FILESDIR}/sigwait.patch:-p1
 
 PORTDOCS=	html
 
Index: devel/valgrind/files/sigwait.patch
===================================================================
--- devel/valgrind/files/sigwait.patch	(nonexistent)
+++ devel/valgrind/files/sigwait.patch	(working copy)
@@ -0,0 +1,46 @@
+--- a/coregrind/m_syswrap/syswrap-freebsd.c	2018-12-12 19:09:24.180201000 +0300
++++ b/coregrind/m_syswrap/syswrap-freebsd.c	2018-12-13 15:13:53.279566000 +0300
+@@ -2537,6 +2537,24 @@
+       POST_MEM_WRITE( ARG2, sizeof(vki_siginfo_t) );
+ }
+ 
++PRE(sys_sigwait)
++{
++   *flags |= SfMayBlock;
++   PRINT("sys_sigwait ( %#lx, %#lx )",
++         ARG1,ARG2);
++   PRE_REG_READ2(long, "sigwait", 
++                 const vki_sigset_t *, set, int *, sig);
++   if (ARG1 != 0) 
++      PRE_MEM_READ(  "sigwait(set)",  ARG1, sizeof(vki_sigset_t));
++   if (ARG2 != 0)
++      PRE_MEM_WRITE( "sigwait(sig)", ARG2, sizeof(int*));
++}
++POST(sys_sigwait)
++{
++   if (ARG2 != 0)
++      POST_MEM_WRITE( ARG2, sizeof(int*));
++}
++
+ #if 0	/* not on freebsd 4.x */
+ PRE(sys_rt_sigqueueinfo)
+ {
+@@ -4309,7 +4340,7 @@
+    BSDX_(__NR___acl_delete_link,	sys___acl_delete_link),		// 427
+ 
+    BSDX_(__NR___acl_aclcheck_link,	sys___acl_aclcheck_link),	// 428
+-   //!sigwait								   429
++   BSDXY(__NR_sigwait,			sys_sigwait),			// 429
+    // thr_create							   430
+    BSDX_(__NR_thr_exit,			sys_thr_exit),			// 431
+ 
+--- a/coregrind/m_syswrap/priv_syswrap-freebsd.h	2018-12-13 15:16:09.551822000 +0300
++++ b/coregrind/m_syswrap/priv_syswrap-freebsd.h	2018-12-13 15:16:16.487873000 +0300
+@@ -181,6 +181,7 @@
+ DECL_TEMPLATE(freebsd, sys_fake_sigreturn);
+ DECL_TEMPLATE(freebsd, sys_sigtimedwait);
+ DECL_TEMPLATE(freebsd, sys_sigwaitinfo);
++DECL_TEMPLATE(freebsd, sys_sigwait);
+ DECL_TEMPLATE(freebsd, sys_getcontext);
+ DECL_TEMPLATE(freebsd, sys_setcontext);
+ DECL_TEMPLATE(freebsd, sys_swapcontext);
Index: devel/valgrind-devel/Makefile
===================================================================
--- devel/valgrind-devel/Makefile	(revision 487542)
+++ devel/valgrind-devel/Makefile	(working copy)
@@ -52,7 +52,8 @@
 		${FILESDIR}/accept4_syscall.patch:-p1 \
 		${FILESDIR}/jail_syscalls.patch:-p1 \
 		${FILESDIR}/kldload_syscalls.patch:-p1 \
-		${FILESDIR}/missing_fcntls.patch:-p1
+		${FILESDIR}/missing_fcntls.patch:-p1 \
+		${FILESDIR}/sigwait.patch:-p1
 
 PORTDOCS=	html
 
Index: devel/valgrind-devel/files/sigwait.patch
===================================================================
--- devel/valgrind-devel/files/sigwait.patch	(nonexistent)
+++ devel/valgrind-devel/files/sigwait.patch	(working copy)
@@ -0,0 +1,46 @@
+--- a/coregrind/m_syswrap/syswrap-freebsd.c	2018-12-12 19:09:24.180201000 +0300
++++ b/coregrind/m_syswrap/syswrap-freebsd.c	2018-12-13 15:13:53.279566000 +0300
+@@ -2537,6 +2537,24 @@
+       POST_MEM_WRITE( ARG2, sizeof(vki_siginfo_t) );
+ }
+ 
++PRE(sys_sigwait)
++{
++   *flags |= SfMayBlock;
++   PRINT("sys_sigwait ( %#lx, %#lx )",
++         ARG1,ARG2);
++   PRE_REG_READ2(long, "sigwait", 
++                 const vki_sigset_t *, set, int *, sig);
++   if (ARG1 != 0) 
++      PRE_MEM_READ(  "sigwait(set)",  ARG1, sizeof(vki_sigset_t));
++   if (ARG2 != 0)
++      PRE_MEM_WRITE( "sigwait(sig)", ARG2, sizeof(int*));
++}
++POST(sys_sigwait)
++{
++   if (ARG2 != 0)
++      POST_MEM_WRITE( ARG2, sizeof(int*));
++}
++
+ #if 0	/* not on freebsd 4.x */
+ PRE(sys_rt_sigqueueinfo)
+ {
+@@ -4309,7 +4340,7 @@
+    BSDX_(__NR___acl_delete_link,	sys___acl_delete_link),		// 427
+ 
+    BSDX_(__NR___acl_aclcheck_link,	sys___acl_aclcheck_link),	// 428
+-   //!sigwait								   429
++   BSDXY(__NR_sigwait,			sys_sigwait),			// 429
+    // thr_create							   430
+    BSDX_(__NR_thr_exit,			sys_thr_exit),			// 431
+ 
+--- a/coregrind/m_syswrap/priv_syswrap-freebsd.h	2018-12-13 15:16:09.551822000 +0300
++++ b/coregrind/m_syswrap/priv_syswrap-freebsd.h	2018-12-13 15:16:16.487873000 +0300
+@@ -181,6 +181,7 @@
+ DECL_TEMPLATE(freebsd, sys_fake_sigreturn);
+ DECL_TEMPLATE(freebsd, sys_sigtimedwait);
+ DECL_TEMPLATE(freebsd, sys_sigwaitinfo);
++DECL_TEMPLATE(freebsd, sys_sigwait);
+ DECL_TEMPLATE(freebsd, sys_getcontext);
+ DECL_TEMPLATE(freebsd, sys_setcontext);
+ DECL_TEMPLATE(freebsd, sys_swapcontext);