Index: head/sys/amd64/amd64/machdep.c
===================================================================
--- head/sys/amd64/amd64/machdep.c
+++ head/sys/amd64/amd64/machdep.c
@@ -581,9 +581,13 @@
 void
 exec_setregs(struct thread *td, struct image_params *imgp, u_long stack)
 {
-	struct trapframe *regs = td->td_frame;
-	struct pcb *pcb = td->td_pcb;
+	struct trapframe *regs;
+	struct pcb *pcb;
+	register_t saved_rflags;
 
+	regs = td->td_frame;
+	pcb = td->td_pcb;
+
 	if (td->td_proc->p_md.md_ldt != NULL)
 		user_ldt_free(td);
 
@@ -593,11 +597,12 @@
 	clear_pcb_flags(pcb, PCB_32BIT);
 	pcb->pcb_initial_fpucw = __INITIAL_FPUCW__;
 
+	saved_rflags = regs->tf_rflags & PSL_T;
 	bzero((char *)regs, sizeof(struct trapframe));
 	regs->tf_rip = imgp->entry_addr;
 	regs->tf_rsp = ((stack - 8) & ~0xFul) + 8;
 	regs->tf_rdi = stack;		/* argv */
-	regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T);
+	regs->tf_rflags = PSL_USER | saved_rflags;
 	regs->tf_ss = _udatasel;
 	regs->tf_cs = _ucodesel;
 	regs->tf_ds = _udatasel;
Index: head/sys/amd64/ia32/ia32_signal.c
===================================================================
--- head/sys/amd64/ia32/ia32_signal.c
+++ head/sys/amd64/ia32/ia32_signal.c
@@ -936,9 +936,13 @@
 void
 ia32_setregs(struct thread *td, struct image_params *imgp, u_long stack)
 {
-	struct trapframe *regs = td->td_frame;
-	struct pcb *pcb = td->td_pcb;
+	struct trapframe *regs;
+	struct pcb *pcb;
+	register_t saved_rflags;
 
+	regs = td->td_frame;
+	pcb = td->td_pcb;
+
 	if (td->td_proc->p_md.md_ldt != NULL)
 		user_ldt_free(td);
 #ifdef COMPAT_43
@@ -949,10 +953,11 @@
 	pcb->pcb_gsbase = 0;
 	pcb->pcb_initial_fpucw = __INITIAL_FPUCW_I386__;
 
+	saved_rflags = regs->tf_rflags & PSL_T;
 	bzero((char *)regs, sizeof(struct trapframe));
 	regs->tf_rip = imgp->entry_addr;
 	regs->tf_rsp = stack;
-	regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T);
+	regs->tf_rflags = PSL_USER | saved_rflags;
 	regs->tf_ss = _udatasel;
 	regs->tf_cs = _ucode32sel;
 	regs->tf_rbx = imgp->ps_strings;
Index: head/sys/amd64/linux/linux_sysvec.c
===================================================================
--- head/sys/amd64/linux/linux_sysvec.c
+++ head/sys/amd64/linux/linux_sysvec.c
@@ -404,9 +404,13 @@
 static void
 linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack)
 {
-	struct trapframe *regs = td->td_frame;
-	struct pcb *pcb = td->td_pcb;
+	struct trapframe *regs;
+	struct pcb *pcb;
+	register_t saved_rflags;
 
+	regs = td->td_frame;
+	pcb = td->td_pcb;
+
 	if (td->td_proc->p_md.md_ldt != NULL)
 		user_ldt_free(td);
 
@@ -416,10 +420,11 @@
 	pcb->pcb_initial_fpucw = __LINUX_NPXCW__;
 	set_pcb_flags(pcb, PCB_FULL_IRET);
 
+	saved_rflags = regs->tf_rflags & PSL_T;
 	bzero((char *)regs, sizeof(struct trapframe));
 	regs->tf_rip = imgp->entry_addr;
 	regs->tf_rsp = stack;
-	regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T);
+	regs->tf_rflags = PSL_USER | saved_rflags;
 	regs->tf_ss = _udatasel;
 	regs->tf_cs = _ucodesel;
 	regs->tf_ds = _udatasel;
Index: head/sys/amd64/linux32/linux32_sysvec.c
===================================================================
--- head/sys/amd64/linux32/linux32_sysvec.c
+++ head/sys/amd64/linux32/linux32_sysvec.c
@@ -719,7 +719,11 @@
 {
 	struct trapframe *regs = td->td_frame;
 	struct pcb *pcb = td->td_pcb;
+	register_t saved_rflags;
 
+	regs = td->td_frame;
+	pcb = td->td_pcb;
+
 	if (td->td_proc->p_md.md_ldt != NULL)
 		user_ldt_free(td);
 
@@ -731,10 +735,11 @@
 	critical_exit();
 	pcb->pcb_initial_fpucw = __LINUX_NPXCW__;
 
+	saved_rflags = regs->tf_rflags & PSL_T;
 	bzero((char *)regs, sizeof(struct trapframe));
 	regs->tf_rip = imgp->entry_addr;
 	regs->tf_rsp = stack;
-	regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T);
+	regs->tf_rflags = PSL_USER | saved_rflags;
 	regs->tf_gs = _ugssel;
 	regs->tf_fs = _ufssel;
 	regs->tf_es = _udatasel;
Index: head/sys/i386/i386/machdep.c
===================================================================
--- head/sys/i386/i386/machdep.c
+++ head/sys/i386/i386/machdep.c
@@ -1104,9 +1104,13 @@
 void
 exec_setregs(struct thread *td, struct image_params *imgp, u_long stack)
 {
-	struct trapframe *regs = td->td_frame;
-	struct pcb *pcb = td->td_pcb;
+	struct trapframe *regs;
+	struct pcb *pcb;
+	register_t saved_eflags;
 
+	regs = td->td_frame;
+	pcb = td->td_pcb;
+
 	/* Reset pc->pcb_gs and %gs before possibly invalidating it. */
 	pcb->pcb_gs = _udatasel;
 	load_gs(_udatasel);
@@ -1127,10 +1131,11 @@
 	set_gsbase(td, 0);
 
 	/* Make sure edx is 0x0 on entry. Linux binaries depend on it. */
+	saved_eflags = regs->tf_eflags & PSL_T;
 	bzero((char *)regs, sizeof(struct trapframe));
 	regs->tf_eip = imgp->entry_addr;
 	regs->tf_esp = stack;
-	regs->tf_eflags = PSL_USER | (regs->tf_eflags & PSL_T);
+	regs->tf_eflags = PSL_USER | saved_eflags;
 	regs->tf_ss = _udatasel;
 	regs->tf_ds = _udatasel;
 	regs->tf_es = _udatasel;