diff --git a/coregrind/Makefile.am b/coregrind/Makefile.am
index e34999b..57fa593 100644
--- a/coregrind/Makefile.am
+++ b/coregrind/Makefile.am
@@ -154,6 +154,7 @@
 	pub_core_libcfile.h	\
 	pub_core_libcprint.h	\
 	pub_core_libcproc.h	\
+	pub_core_libcsetjmp.h	\
 	pub_core_libcsignal.h	\
 	pub_core_mach.h		\
 	pub_core_machine.h	\
@@ -239,6 +240,7 @@
 	m_libcfile.c \
 	m_libcprint.c \
 	m_libcproc.c \
+	m_libcsetjmp.c \
 	m_libcsignal.c \
 	m_machine.c \
 	m_main.c \
diff --git a/coregrind/m_coredump/coredump-elf.c b/coregrind/m_coredump/coredump-elf.c
index ef27bb5..fe04c5b 100644
--- a/coregrind/m_coredump/coredump-elf.c
+++ b/coregrind/m_coredump/coredump-elf.c
@@ -42,6 +42,7 @@
 #include "pub_core_libcproc.h"    // VG_(geteuid), VG_(getegid)
 #include "pub_core_libcassert.h"  // VG_(exit), vg_assert
 #include "pub_core_mallocfree.h"  // VG_(malloc), VG_(free)
+#include "pub_core_libcsetjmp.h"  // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_xarray.h"
 #include "pub_core_clientstate.h"
diff --git a/coregrind/m_debugger.c b/coregrind/m_debugger.c
index 0638755..fe2c7f2 100644
--- a/coregrind/m_debugger.c
+++ b/coregrind/m_debugger.c
@@ -30,6 +30,7 @@
 
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
+#include "pub_core_libcsetjmp.h"
 #include "pub_core_threadstate.h"
 #include "pub_core_xarray.h"
 #include "pub_core_clientstate.h"
diff --git a/coregrind/m_debuginfo/debuginfo.c b/coregrind/m_debuginfo/debuginfo.c
index 9e67d55..8e431ad 100644
--- a/coregrind/m_debuginfo/debuginfo.c
+++ b/coregrind/m_debuginfo/debuginfo.c
@@ -31,6 +31,7 @@
 
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
+#include "pub_core_libcsetjmp.h" // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_debuginfo.h"  /* self */
 #include "pub_core_demangle.h"
diff --git a/coregrind/m_debuginfo/readdwarf3.c b/coregrind/m_debuginfo/readdwarf3.c
index 4d75afb..918c425 100644
--- a/coregrind/m_debuginfo/readdwarf3.c
+++ b/coregrind/m_debuginfo/readdwarf3.c
@@ -139,6 +139,7 @@
 #include "pub_core_libcbase.h"
 #include "pub_core_libcassert.h"
 #include "pub_core_libcprint.h"
+#include "pub_core_libcsetjmp.h"   // setjmp facilities
 #include "pub_core_options.h"
 #include "pub_core_tooliface.h"    /* VG_(needs) */
 #include "pub_core_xarray.h"
@@ -3952,18 +3953,14 @@
 /*---                                                      ---*/
 /*------------------------------------------------------------*/
 
-/* --- !!! --- EXTERNAL HEADERS start --- !!! --- */
-#include <setjmp.h>   /* For jmp_buf */
-/* --- !!! --- EXTERNAL HEADERS end --- !!! --- */
-
-static Bool    d3rd_jmpbuf_valid  = False;
-static HChar*  d3rd_jmpbuf_reason = NULL;
-static jmp_buf d3rd_jmpbuf;
+static Bool               d3rd_jmpbuf_valid  = False;
+static HChar*             d3rd_jmpbuf_reason = NULL;
+static VG_MINIMAL_JMP_BUF d3rd_jmpbuf;
 
 static __attribute__((noreturn)) void barf ( HChar* reason ) {
    vg_assert(d3rd_jmpbuf_valid);
    d3rd_jmpbuf_reason = reason;
-   __builtin_longjmp(&d3rd_jmpbuf, 1);
+   VG_MINIMAL_LONGJMP(d3rd_jmpbuf);
    /*NOTREACHED*/
    vg_assert(0);
 }
@@ -3991,7 +3988,7 @@
    vg_assert(d3rd_jmpbuf_reason == NULL);
 
    d3rd_jmpbuf_valid = True;
-   jumped = __builtin_setjmp(&d3rd_jmpbuf);
+   jumped = VG_MINIMAL_SETJMP(d3rd_jmpbuf);
    if (jumped == 0) {
       /* try this ... */
       new_dwarf3_reader_wrk( di, barf,
diff --git a/coregrind/m_errormgr.c b/coregrind/m_errormgr.c
index d043747..bb3247a 100644
--- a/coregrind/m_errormgr.c
+++ b/coregrind/m_errormgr.c
@@ -30,6 +30,7 @@
 
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
+#include "pub_core_libcsetjmp.h"
 #include "pub_core_threadstate.h"      // For VG_N_THREADS
 #include "pub_core_debugger.h"
 #include "pub_core_debuginfo.h"
diff --git a/coregrind/m_execontext.c b/coregrind/m_execontext.c
index fcb45d7..80574fe 100644
--- a/coregrind/m_execontext.c
+++ b/coregrind/m_execontext.c
@@ -37,6 +37,7 @@
 #include "pub_core_stacktrace.h"
 #include "pub_core_machine.h"       // VG_(get_IP)
 #include "pub_core_vki.h"           // To keep pub_core_threadstate.h happy
+#include "pub_core_libcsetjmp.h"    // Ditto
 #include "pub_core_threadstate.h"   // VG_(is_valid_tid)
 #include "pub_core_execontext.h"    // self
 
diff --git a/coregrind/m_initimg/initimg-linux.c b/coregrind/m_initimg/initimg-linux.c
index 0976998..4b9f0dd 100644
--- a/coregrind/m_initimg/initimg-linux.c
+++ b/coregrind/m_initimg/initimg-linux.c
@@ -48,6 +48,7 @@
 #include "pub_core_options.h"
 #include "pub_core_syscall.h"
 #include "pub_core_tooliface.h"       /* VG_TRACK */
+#include "pub_core_libcsetjmp.h"      // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"     /* ThreadArchState */
 #include "priv_initimg_pathscan.h"
 #include "pub_core_initimg.h"         /* self */
diff --git a/coregrind/m_initimg/initimg-pathscan.c b/coregrind/m_initimg/initimg-pathscan.c
index df47316..cca5817 100644
--- a/coregrind/m_initimg/initimg-pathscan.c
+++ b/coregrind/m_initimg/initimg-pathscan.c
@@ -44,7 +44,6 @@
 #include "pub_core_ume.h"
 #include "pub_core_options.h"
 #include "pub_core_tooliface.h"       /* VG_TRACK */
-#include "pub_core_threadstate.h"     /* ThreadArchState */
 #include "pub_core_initimg.h"         /* self */
 
 #include "priv_initimg_pathscan.h"
diff --git a/coregrind/m_libcassert.c b/coregrind/m_libcassert.c
index 63e3f1c..49c5ad6 100644
--- a/coregrind/m_libcassert.c
+++ b/coregrind/m_libcassert.c
@@ -31,6 +31,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_libcbase.h"
 #include "pub_core_libcassert.h"
diff --git a/coregrind/m_libcsetjmp.c b/coregrind/m_libcsetjmp.c
new file mode 100644
index 0000000..8d1c2c2
--- /dev/null
+++ b/coregrind/m_libcsetjmp.c
@@ -0,0 +1,44 @@
+
+/*--------------------------------------------------------------------*/
+/*--- A minimal setjmp/longjmp implementation.      m_libcsetjmp.c ---*/
+/*--------------------------------------------------------------------*/
+ 
+/*
+   This file is part of Valgrind, a dynamic binary instrumentation
+   framework.
+
+   Copyright (C) 2010-2010 Mozilla Inc
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307, USA.
+
+   The GNU General Public License is contained in the file COPYING.
+*/
+
+/* Contributed by Julian Seward <jseward@acm.org> */
+
+
+#include "pub_core_basics.h"
+#include "pub_core_libcsetjmp.h"    /* self */
+
+
+/* See include/pub_tool_libcsetjmp.h for background and rationale. */
+
+/* No alternative implementations at present. */
+
+
+/*--------------------------------------------------------------------*/
+/*--- end                                                          ---*/
+/*--------------------------------------------------------------------*/
diff --git a/coregrind/m_machine.c b/coregrind/m_machine.c
index 042d985..521569d 100644
--- a/coregrind/m_machine.c
+++ b/coregrind/m_machine.c
@@ -30,6 +30,7 @@
 
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
+#include "pub_core_libcsetjmp.h"   // setjmp facilities
 #include "pub_core_threadstate.h"
 #include "pub_core_libcassert.h"
 #include "pub_core_libcbase.h"
@@ -418,11 +419,14 @@
 /* fixs390: anything for s390x here ? */
 
 /* For hwcaps detection on ppc32/64 and arm we'll need to do SIGILL
-   testing, so we need a jmp_buf. */
-#if defined(VGA_ppc32) || defined(VGA_ppc64) || defined(VGA_arm) || defined(VGA_s390x)
-#include <setjmp.h> // For jmp_buf
-static jmp_buf env_unsup_insn;
-static void handler_unsup_insn ( Int x ) { __builtin_longjmp(env_unsup_insn,1); }
+   testing, so we need a VG_MINIMAL_JMP_BUF. */
+#if defined(VGA_ppc32) || defined(VGA_ppc64) \
+    || defined(VGA_arm) || defined(VGA_s390x)
+#include "pub_tool_libcsetjmp.h"
+static VG_MINIMAL_JMP_BUF env_unsup_insn;
+static void handler_unsup_insn ( Int x ) {
+   VG_MINIMAL_LONGJMP(env_unsup_insn);
+}
 #endif
 
 
@@ -462,7 +466,7 @@
    vg_assert(dcbz_szB == 32 || dcbz_szB == 64 || dcbz_szB == 128);
 
    /* dcbzl clears 128B on G5/PPC970, and usually 32B on other platforms */
-   if (__builtin_setjmp(env_unsup_insn)) {
+   if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
       dcbzl_szB = 0; /* indicates unsupported */
    }
    else {
@@ -689,7 +693,7 @@
 
      /* standard FP insns */
      have_F = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_F = False;
      } else {
         __asm__ __volatile__(".long 0xFC000090"); /*fmr 0,0 */
@@ -697,7 +701,7 @@
 
      /* Altivec insns */
      have_V = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_V = False;
      } else {
         /* Unfortunately some older assemblers don't speak Altivec (or
@@ -710,7 +714,7 @@
 
      /* General-Purpose optional (fsqrt, fsqrts) */
      have_FX = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_FX = False;
      } else {
         __asm__ __volatile__(".long 0xFC00002C"); /*fsqrt 0,0 */
@@ -718,7 +722,7 @@
 
      /* Graphics optional (stfiwx, fres, frsqrte, fsel) */
      have_GX = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_GX = False;
      } else {
         __asm__ __volatile__(".long 0xFC000034"); /* frsqrte 0,0 */
@@ -808,7 +812,7 @@
 
      /* standard FP insns */
      have_F = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_F = False;
      } else {
         __asm__ __volatile__("fmr 0,0");
@@ -816,7 +820,7 @@
 
      /* Altivec insns */
      have_V = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_V = False;
      } else {
         __asm__ __volatile__(".long 0x10000484"); /*vor 0,0,0*/
@@ -824,7 +828,7 @@
 
      /* General-Purpose optional (fsqrt, fsqrts) */
      have_FX = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_FX = False;
      } else {
         __asm__ __volatile__(".long 0xFC00002C"); /*fsqrt 0,0*/
@@ -832,7 +836,7 @@
 
      /* Graphics optional (stfiwx, fres, frsqrte, fsel) */
      have_GX = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_GX = False;
      } else {
         __asm__ __volatile__(".long 0xFC000034"); /*frsqrte 0,0*/
@@ -899,7 +903,7 @@
         is not supported on z900. */
 
      have_LDISP = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_LDISP = False;
      } else {
        /* BASR loads the address of the next insn into r1. Needed to avoid
@@ -910,7 +914,7 @@
      }
 
      have_EIMM = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_EIMM = False;
      } else {
         __asm__ __volatile__(".long  0xc0090000\n\t"  /* iilf r0,0 */
@@ -918,7 +922,7 @@
      }
 
      have_GIE = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_GIE = False;
      } else {
         __asm__ __volatile__(".long  0xc2010000\n\t"  /* msfi r0,0 */
@@ -926,7 +930,7 @@
      }
 
      have_DFP = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_DFP = False;
      } else {
         __asm__ __volatile__(".long 0xb3d20000"
@@ -1004,7 +1008,7 @@
 
      /* VFP insns */
      have_VFP = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_VFP = False;
      } else {
         __asm__ __volatile__(".word 0xEEB02B42"); /* VMOV.F64 d2, d2 */
@@ -1016,7 +1020,7 @@
 
      /* NEON insns */
      have_NEON = True;
-     if (__builtin_setjmp(env_unsup_insn)) {
+     if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
         have_NEON = False;
      } else {
         __asm__ __volatile__(".word 0xF2244154"); /* VMOV q2, q2 */
@@ -1026,7 +1030,7 @@
      archlevel = 5; /* v5 will be base level */
      if (archlevel < 7) {
         archlevel = 7;
-        if (__builtin_setjmp(env_unsup_insn)) {
+        if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
            archlevel = 5;
         } else {
            __asm__ __volatile__(".word 0xF45FF000"); /* PLI [PC,#-0] */
@@ -1034,7 +1038,7 @@
      }
      if (archlevel < 6) {
         archlevel = 6;
-        if (__builtin_setjmp(env_unsup_insn)) {
+        if (VG_MINIMAL_SETJMP(env_unsup_insn)) {
            archlevel = 5;
         } else {
            __asm__ __volatile__(".word 0xE6822012"); /* PKHBT r2, r2, r2 */
diff --git a/coregrind/m_main.c b/coregrind/m_main.c
index e9bfe20..0598424 100644
--- a/coregrind/m_main.c
+++ b/coregrind/m_main.c
@@ -31,6 +31,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_xarray.h"
 #include "pub_core_clientstate.h"
diff --git a/coregrind/m_mallocfree.c b/coregrind/m_mallocfree.c
index 4054c96..6199f16 100644
--- a/coregrind/m_mallocfree.c
+++ b/coregrind/m_mallocfree.c
@@ -38,6 +38,7 @@
 #include "pub_core_libcprint.h"
 #include "pub_core_mallocfree.h"
 #include "pub_core_options.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"   // For VG_INVALID_THREADID
 #include "pub_core_tooliface.h"
 #include "valgrind.h"
diff --git a/coregrind/m_scheduler/scheduler.c b/coregrind/m_scheduler/scheduler.c
index 200adae..f49a4cf 100644
--- a/coregrind/m_scheduler/scheduler.c
+++ b/coregrind/m_scheduler/scheduler.c
@@ -61,6 +61,7 @@
 #include "pub_core_debuglog.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"    // __NR_sched_yield
+#include "pub_core_libcsetjmp.h"   // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_clreq.h"         // for VG_USERREQ__*
@@ -581,7 +582,7 @@
    do {									\
       ThreadState * volatile _qq_tst = VG_(get_ThreadState)(tid);	\
 									\
-      (jumped) = __builtin_setjmp(_qq_tst->sched_jmpbuf);               \
+      (jumped) = VG_MINIMAL_SETJMP(_qq_tst->sched_jmpbuf);              \
       if ((jumped) == 0) {						\
 	 vg_assert(!_qq_tst->sched_jmpbuf_valid);			\
 	 _qq_tst->sched_jmpbuf_valid = True;				\
diff --git a/coregrind/m_sigframe/sigframe-amd64-linux.c b/coregrind/m_sigframe/sigframe-amd64-linux.c
index b234e3a..710a34b 100644
--- a/coregrind/m_sigframe/sigframe-amd64-linux.c
+++ b/coregrind/m_sigframe/sigframe-amd64-linux.c
@@ -33,6 +33,7 @@
 
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_libcbase.h"
diff --git a/coregrind/m_sigframe/sigframe-arm-linux.c b/coregrind/m_sigframe/sigframe-arm-linux.c
index 01c1c05..4767700 100644
--- a/coregrind/m_sigframe/sigframe-arm-linux.c
+++ b/coregrind/m_sigframe/sigframe-arm-linux.c
@@ -38,6 +38,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_libcbase.h"
diff --git a/coregrind/m_sigframe/sigframe-ppc32-linux.c b/coregrind/m_sigframe/sigframe-ppc32-linux.c
index 9710b37..f19f71f 100644
--- a/coregrind/m_sigframe/sigframe-ppc32-linux.c
+++ b/coregrind/m_sigframe/sigframe-ppc32-linux.c
@@ -36,6 +36,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_libcbase.h"
diff --git a/coregrind/m_sigframe/sigframe-ppc64-linux.c b/coregrind/m_sigframe/sigframe-ppc64-linux.c
index 5c6198b..2e6dc0f 100644
--- a/coregrind/m_sigframe/sigframe-ppc64-linux.c
+++ b/coregrind/m_sigframe/sigframe-ppc64-linux.c
@@ -36,6 +36,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_libcbase.h"
diff --git a/coregrind/m_sigframe/sigframe-s390x-linux.c b/coregrind/m_sigframe/sigframe-s390x-linux.c
index e5e3801..9d3afca 100644
--- a/coregrind/m_sigframe/sigframe-s390x-linux.c
+++ b/coregrind/m_sigframe/sigframe-s390x-linux.c
@@ -33,6 +33,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_libcbase.h"
diff --git a/coregrind/m_sigframe/sigframe-x86-linux.c b/coregrind/m_sigframe/sigframe-x86-linux.c
index 6b61055..079fc71 100644
--- a/coregrind/m_sigframe/sigframe-x86-linux.c
+++ b/coregrind/m_sigframe/sigframe-x86-linux.c
@@ -33,6 +33,7 @@
 
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h" /* find_segment */
 #include "pub_core_libcbase.h"
diff --git a/coregrind/m_signals.c b/coregrind/m_signals.c
index 65fc40a..105c02a 100644
--- a/coregrind/m_signals.c
+++ b/coregrind/m_signals.c
@@ -197,6 +197,7 @@
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
 #include "pub_core_debuglog.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_xarray.h"
 #include "pub_core_clientstate.h"
@@ -1779,7 +1780,7 @@
    if (tst->sched_jmpbuf_valid) {
       /* Can't continue; must longjmp back to the scheduler and thus
          enter the sighandler immediately. */
-      __builtin_longjmp(tst->sched_jmpbuf, True);
+      VG_MINIMAL_LONGJMP(tst->sched_jmpbuf);
    }
 }
 
diff --git a/coregrind/m_stacktrace.c b/coregrind/m_stacktrace.c
index 707b470..7984de3 100644
--- a/coregrind/m_stacktrace.c
+++ b/coregrind/m_stacktrace.c
@@ -30,6 +30,7 @@
 
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_debuginfo.h"     // XXX: circular dependency
 #include "pub_core_aspacemgr.h"     // For VG_(is_addressable)()
diff --git a/coregrind/m_syswrap/syswrap-amd64-linux.c b/coregrind/m_syswrap/syswrap-amd64-linux.c
index ecb3d00..ece1a73 100644
--- a/coregrind/m_syswrap/syswrap-amd64-linux.c
+++ b/coregrind/m_syswrap/syswrap-amd64-linux.c
@@ -33,6 +33,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_debuglog.h"
diff --git a/coregrind/m_syswrap/syswrap-arm-linux.c b/coregrind/m_syswrap/syswrap-arm-linux.c
index 65b3923..0765089 100644
--- a/coregrind/m_syswrap/syswrap-arm-linux.c
+++ b/coregrind/m_syswrap/syswrap-arm-linux.c
@@ -35,6 +35,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_debuglog.h"
diff --git a/coregrind/m_syswrap/syswrap-generic.c b/coregrind/m_syswrap/syswrap-generic.c
index 9f4025c..4362140 100644
--- a/coregrind/m_syswrap/syswrap-generic.c
+++ b/coregrind/m_syswrap/syswrap-generic.c
@@ -34,6 +34,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_debuginfo.h"     // VG_(di_notify_*)
 #include "pub_core_aspacemgr.h"
diff --git a/coregrind/m_syswrap/syswrap-linux-variants.c b/coregrind/m_syswrap/syswrap-linux-variants.c
index 27463ed..dc433ec 100644
--- a/coregrind/m_syswrap/syswrap-linux-variants.c
+++ b/coregrind/m_syswrap/syswrap-linux-variants.c
@@ -48,6 +48,7 @@
 
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
+#include "pub_core_libcsetjmp.h"   // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_debuginfo.h"    // VG_(di_notify_*)
diff --git a/coregrind/m_syswrap/syswrap-linux.c b/coregrind/m_syswrap/syswrap-linux.c
index 35f8ee6..df5654a 100644
--- a/coregrind/m_syswrap/syswrap-linux.c
+++ b/coregrind/m_syswrap/syswrap-linux.c
@@ -33,6 +33,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"   // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_debuginfo.h"    // VG_(di_notify_*)
diff --git a/coregrind/m_syswrap/syswrap-main.c b/coregrind/m_syswrap/syswrap-main.c
index 4d33eb8..cff0543 100644
--- a/coregrind/m_syswrap/syswrap-main.c
+++ b/coregrind/m_syswrap/syswrap-main.c
@@ -34,6 +34,7 @@
 #include "pub_core_aspacemgr.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_libcbase.h"
 #include "pub_core_libcassert.h"
@@ -2266,7 +2267,7 @@
    sci->status.what = SsIdle;
 
    vg_assert(tst->sched_jmpbuf_valid);
-   __builtin_longjmp(tst->sched_jmpbuf, True);
+   VG_MINIMAL_LONGJMP(tst->sched_jmpbuf, True);
 
    /* NOTREACHED */
    vg_assert(0);
diff --git a/coregrind/m_syswrap/syswrap-ppc32-linux.c b/coregrind/m_syswrap/syswrap-ppc32-linux.c
index ca37a5a..9baf8d8 100644
--- a/coregrind/m_syswrap/syswrap-ppc32-linux.c
+++ b/coregrind/m_syswrap/syswrap-ppc32-linux.c
@@ -33,6 +33,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_debuglog.h"
diff --git a/coregrind/m_syswrap/syswrap-ppc64-linux.c b/coregrind/m_syswrap/syswrap-ppc64-linux.c
index 9e9456a..1e9e96c 100644
--- a/coregrind/m_syswrap/syswrap-ppc64-linux.c
+++ b/coregrind/m_syswrap/syswrap-ppc64-linux.c
@@ -33,6 +33,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_debuglog.h"
diff --git a/coregrind/m_syswrap/syswrap-s390x-linux.c b/coregrind/m_syswrap/syswrap-s390x-linux.c
index eb2f290..02acbf4 100644
--- a/coregrind/m_syswrap/syswrap-s390x-linux.c
+++ b/coregrind/m_syswrap/syswrap-s390x-linux.c
@@ -34,6 +34,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_debuglog.h"
diff --git a/coregrind/m_syswrap/syswrap-x86-linux.c b/coregrind/m_syswrap/syswrap-x86-linux.c
index c0a8b2b..4b52656 100644
--- a/coregrind/m_syswrap/syswrap-x86-linux.c
+++ b/coregrind/m_syswrap/syswrap-x86-linux.c
@@ -38,6 +38,7 @@
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
 #include "pub_core_vkiscnums.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_aspacemgr.h"
 #include "pub_core_debuglog.h"
diff --git a/coregrind/m_threadstate.c b/coregrind/m_threadstate.c
index d047110..c45ce21 100644
--- a/coregrind/m_threadstate.c
+++ b/coregrind/m_threadstate.c
@@ -30,6 +30,7 @@
 
 #include "pub_core_basics.h"
 #include "pub_core_vki.h"
+#include "pub_core_libcsetjmp.h"    // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"
 #include "pub_core_libcassert.h"
 
diff --git a/coregrind/m_translate.c b/coregrind/m_translate.c
index fae4854..5fa2dd1 100644
--- a/coregrind/m_translate.c
+++ b/coregrind/m_translate.c
@@ -53,6 +53,7 @@
 #include "pub_core_dispatch.h" // VG_(run_innerloop__dispatch_{un}profiled)
                                // VG_(run_a_noredir_translation__return_point)
 
+#include "pub_core_libcsetjmp.h"   // to keep _threadstate.h happy
 #include "pub_core_threadstate.h"  // VexGuestArchState
 #include "pub_core_trampoline.h"   // VG_(ppctoc_magic_redirect_return_stub)
 
diff --git a/coregrind/pub_core_basics.h b/coregrind/pub_core_basics.h
index 0718c82..760cccd 100644
--- a/coregrind/pub_core_basics.h
+++ b/coregrind/pub_core_basics.h
@@ -64,9 +64,6 @@
 #  error Unknown arch
 #endif
 
-// For jmp_buf
-#include <setjmp.h>
-
 
 /* ---------------------------------------------------------------------
    A struct to hold starting values for stack unwinding.
diff --git a/coregrind/pub_core_libcsetjmp.h b/coregrind/pub_core_libcsetjmp.h
new file mode 100644
index 0000000..215eacc
--- /dev/null
+++ b/coregrind/pub_core_libcsetjmp.h
@@ -0,0 +1,49 @@
+
+/*--------------------------------------------------------------------*/
+/*--- A minimal setjmp/longjmp facility.     pub_core_libcsetjmp.h ---*/
+/*--------------------------------------------------------------------*/
+
+/*
+   This file is part of Valgrind, a dynamic binary instrumentation
+   framework.
+
+   Copyright (C) 2010-2010 Mozilla Inc
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307, USA.
+
+   The GNU General Public License is contained in the file COPYING.
+*/
+
+/* Contributed by Julian Seward <jseward@acm.org> */
+
+#ifndef __PUB_CORE_LIBCSETJMP_H
+#define __PUB_CORE_LIBCSETJMP_H
+
+//--------------------------------------------------------------------
+// PURPOSE: Provides a minimal setjmp/longjmp facility, that saves/
+// restores integer registers, but not necessarily anything more.
+//--------------------------------------------------------------------
+
+// No core-only exports; everything in this module is visible to both
+// the core and tools.
+
+#include "pub_tool_libcsetjmp.h"
+
+#endif   // __PUB_CORE_LIBCSETJMP_H
+
+/*--------------------------------------------------------------------*/
+/*--- end                                    pub_core_libcsetjmp.h ---*/
+/*--------------------------------------------------------------------*/
diff --git a/coregrind/pub_core_threadstate.h b/coregrind/pub_core_threadstate.h
index a784d0e..639ef73 100644
--- a/coregrind/pub_core_threadstate.h
+++ b/coregrind/pub_core_threadstate.h
@@ -355,8 +355,8 @@
    ThreadOSstate os_state;
 
    /* Per-thread jmp_buf to resume scheduler after a signal */
-   Bool    sched_jmpbuf_valid;
-   jmp_buf sched_jmpbuf;
+   Bool               sched_jmpbuf_valid;
+   VG_MINIMAL_JMP_BUF sched_jmpbuf;
 }
 ThreadState;
 
diff --git a/include/Makefile.am b/include/Makefile.am
index 3a1adc0..ae1f0ca 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -18,6 +18,7 @@
 	pub_tool_libcfile.h 		\
 	pub_tool_libcprint.h 		\
 	pub_tool_libcproc.h 		\
+	pub_tool_libcsetjmp.h 		\
 	pub_tool_libcsignal.h 		\
 	pub_tool_machine.h 		\
 	pub_tool_mallocfree.h 		\
diff --git a/include/pub_tool_libcsetjmp.h b/include/pub_tool_libcsetjmp.h
new file mode 100644
index 0000000..faf8d37
--- /dev/null
+++ b/include/pub_tool_libcsetjmp.h
@@ -0,0 +1,76 @@
+
+/*--------------------------------------------------------------------*/
+/*--- A minimal setjmp/longjmp facility.     pub_tool_libcsetjmp.h ---*/
+/*--------------------------------------------------------------------*/
+
+/*
+   This file is part of Valgrind, a dynamic binary instrumentation
+   framework.
+
+   Copyright (C) 2010-2010 Mozilla Inc
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307, USA.
+
+   The GNU General Public License is contained in the file COPYING.
+*/
+
+/* Contributed by Julian Seward <jseward@acm.org> */
+
+#ifndef __PUB_TOOL_LIBCSETJMP_H
+#define __PUB_TOOL_LIBCSETJMP_H
+
+//--------------------------------------------------------------------
+// PURPOSE: Provides a minimal setjmp/longjmp facility, that saves/
+// restores integer registers, but not necessarily anything more.
+//--------------------------------------------------------------------
+
+
+/* This provides an extremely minimal setjmp/longjmp facility, in
+   which only the host's integer registers are saved/restored.  Or at
+   least, that is the minimal guaranteed functionality.
+
+   Until Apr 2011 we used __builtin_setjmp and __builtin_longjmp, but
+   it appears that that is not always correctly implemented.  See
+   https://bugs.kde.org/show_bug.cgi?id=259977.  So this module wraps
+   those functions up and facilitates replacing them with our own
+   implementations where necessary.
+*/
+
+/* --- !!! --- EXTERNAL HEADERS start --- !!! --- */
+#include <setjmp.h>
+/* --- !!! --- EXTERNAL HEADERS end --- !!! --- */
+
+
+/* Don't use jmp_buf, __builtin_setjmp or __builtin_longjmp directly.
+   They don't always work reliably.  Instead use these macros, which
+   provide the opportunity to supply alternative implementations as
+   necessary.
+
+   Note that the abstraction is done with macros (ick) rather than
+   functions and typedefs, since wrapping __builtin_setjmp up in a
+   second function (eg, VG_(minimal_setjmp)) doesn't seem to work for
+   whatever reason -- returns via a VG_(minimal_longjmp) go wrong.
+*/
+#define VG_MINIMAL_JMP_BUF        jmp_buf
+#define VG_MINIMAL_SETJMP(_env)   __builtin_setjmp((_env))
+#define VG_MINIMAL_LONGJMP(_env)  __builtin_longjmp((_env),1)
+
+
+#endif   // __PUB_TOOL_LIBCSETJMP_H
+
+/*--------------------------------------------------------------------*/
+/*--- end                                    pub_tool_libcsetjmp.h ---*/
+/*--------------------------------------------------------------------*/
diff --git a/memcheck/mc_leakcheck.c b/memcheck/mc_leakcheck.c
index 13b8de3..bdf0fc6 100644
--- a/memcheck/mc_leakcheck.c
+++ b/memcheck/mc_leakcheck.c
@@ -43,12 +43,11 @@
 #include "pub_tool_options.h"
 #include "pub_tool_oset.h"
 #include "pub_tool_signals.h"
+#include "pub_tool_libcsetjmp.h"    // setjmp facilities
 #include "pub_tool_tooliface.h"     // Needed for mc_include.h
 
 #include "mc_include.h"
 
-#include <setjmp.h>                 // For jmp_buf
-
 /*------------------------------------------------------------*/
 /*--- An overview of leak checking.                        ---*/
 /*------------------------------------------------------------*/
@@ -636,7 +635,7 @@
 }
 
 
-static jmp_buf memscan_jmpbuf;
+static VG_MINIMAL_JMP_BUF memscan_jmpbuf;
 
 static
 void scan_all_valid_memory_catcher ( Int sigNo, Addr addr )
@@ -644,7 +643,7 @@
    if (0)
       VG_(printf)("OUCH! sig=%d addr=%#lx\n", sigNo, addr);
    if (sigNo == VKI_SIGSEGV || sigNo == VKI_SIGBUS)
-      __builtin_longjmp(memscan_jmpbuf, 1);
+      VG_MINIMAL_LONGJMP(memscan_jmpbuf);
 }
 
 // Scan a block of memory between [start, start+len).  This range may
@@ -686,7 +685,7 @@
          }
       }
 
-      if (__builtin_setjmp(memscan_jmpbuf) == 0) {
+      if (VG_MINIMAL_SETJMP(memscan_jmpbuf) == 0) {
          if ( MC_(is_valid_aligned_word)(ptr) ) {
             lc_scanned_szB += sizeof(Addr);
             addr = *(Addr *)ptr;