diff --git a/classes/external-toolchain.bbclass b/classes/external-toolchain.bbclass
index 0ff818c..78eeb3a 100644
--- a/classes/external-toolchain.bbclass
+++ b/classes/external-toolchain.bbclass
@@ -23,6 +23,7 @@ LICENSE = "CLOSED"
 LIC_FILES_CHKSUM = "${COMMON_LIC_CHKSUM}"
 
 EXTERNAL_TOOLCHAIN_SYSROOT ?= "${@external_run(d, 'gcc', *(TARGET_CC_ARCH.split() + ['-print-sysroot'])).rstrip()}"
+EXTERNAL_TOOLCHAIN_LIBROOT ?= "${@external_run(d, 'gcc', *(TARGET_CC_ARCH.split() + ['-print-file-name=crtbegin.o'])).rstrip().replace('/crtbegin.o', '')}"
 
 EXTERNAL_INSTALL_SOURCE_PATHS = "\
     ${EXTERNAL_TOOLCHAIN_SYSROOT} \
@@ -163,7 +164,11 @@ def expand_paths(pathnames, mirrors):
         expanded_paths = [pathname]
 
         for search, replace in mirrors:
-            new_pathname = re.sub(search, replace, pathname, count=1)
+            try:
+                new_pathname = re.sub(search, replace, pathname, count=1)
+            except re.error as exc:
+                bb.warn("Invalid pattern for `%s`" % search)
+                continue
             if new_pathname != pathname:
                 expanded_paths.append(new_pathname)
 
diff --git a/core/recipes-devtools/gcc/gcc_%.bbappend b/core/recipes-devtools/gcc/gcc_%.bbappend
new file mode 100644
index 0000000..0df59d8
--- /dev/null
+++ b/core/recipes-devtools/gcc/gcc_%.bbappend
@@ -0,0 +1,10 @@
+# FIXME: resolve gcc version mismatch issues with ${libdir}/gcc/*/<version>
+# filesystem paths
+python () {
+    if d.getVar('TCMODE', True).startswith('external-sourcery'):
+        # unwind.h will come from libgcc-external, we don't want to try to pull it
+        # from the cross area of the sysroot
+        inst = d.getVar('do_install', False).splitlines()
+        inst = filter(lambda l: not ('unwind.h' in l and '${STAGING_LIBDIR_NATIVE}' in l), inst)
+        d.setVar('do_install', '\n'.join(inst))
+}
diff --git a/recipes-external/gcc/gcc-runtime-external.bb b/recipes-external/gcc/gcc-runtime-external.bb
index f3f496e..ac962ce 100644
--- a/recipes-external/gcc/gcc-runtime-external.bb
+++ b/recipes-external/gcc/gcc-runtime-external.bb
@@ -54,9 +54,15 @@ PACKAGES =+ "\
 SUMMARY_libitm = "The Transactional Memory runtime library"
 SUMMARY_libitm-dev = "${SUMMARY_libitm} - development files"
 
+external_libroot = "${@os.path.realpath('${EXTERNAL_TOOLCHAIN_LIBROOT}').replace(os.path.realpath('${EXTERNAL_TOOLCHAIN}') + '/', '/')}"
+FILES_MIRRORS =. "\
+    ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/|${external_libroot}/\n \
+    ${includedir}/c\+\+/${GCC_VERSION}/${TARGET_SYS}/|${includedir}/c++/${GCC_VERSION}/${EXTERNAL_TARGET_SYS}/\n \
+"
+
 FILES_libstdc++ = "${libdir}/libstdc++${SOLIBS}"
 FILES_libstdc++-dev = "${libdir}/libstdc++${SOLIBSDEV} \
-                       ${includedir}/c++/${GCC_VERSION}"
+                       ${includedir}/c++/${GCC_VERSION}/${TARGET_SYS}"
 FILES_libstdc++-staticdev = "${libdir}/libstdc++.a \
                              ${libdir}/libsupc++.a"
 FILES_libatomic = "${libdir}/libatomic${SOLIBS}"
@@ -84,14 +90,16 @@ FILES_libmudflap = "${libdir}/libmudflap${SOLIBS}"
 FILES_libmudflap-dev = "${libdir}/libmudflap${SOLIBSDEV}"
 FILES_libmudflap-staticdev = "${libdir}/libmudflap.a"
 FILES_libquadmath = "${libdir}/libquadmath${SOLIBS}"
-FILES_libquadmath-dev = "${libdir}/libquadmath${SOLIBSDEV}"
+FILES_libquadmath-dev = "${libdir}/libquadmath${SOLIBSDEV} \
+                         ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/include/quadmath*"
 FILES_libquadmath-staticdev = "${libdir}/libquadmath.a"
 FILES_libssp = "${libdir}/libssp${SOLIBS}"
 FILES_libssp-dev = "${libdir}/libssp${SOLIBSDEV} \
-                    ${libdir}/gcc/*/*/include/ssp"
+                    ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/include/ssp"
 FILES_libssp-staticdev = "${libdir}/libssp.a"
 FILES_libgomp = "${libdir}/libgomp${SOLIBS}"
-FILES_libgomp-dev = "${libdir}/libgomp${SOLIBSDEV}"
+FILES_libgomp-dev = "${libdir}/libgomp${SOLIBSDEV} \
+                     ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/include/omp.h"
 FILES_libgomp-staticdev = "${libdir}/libgomp.a"
 FILES_libitm = "${libdir}/libitm${SOLIBS}"
 FILES_libitm-dev = "${libdir}/libitm${SOLIBSDEV}"
diff --git a/recipes-external/gcc/libgcc-external.bb b/recipes-external/gcc/libgcc-external.bb
index 91a1984..1c01ae1 100644
--- a/recipes-external/gcc/libgcc-external.bb
+++ b/recipes-external/gcc/libgcc-external.bb
@@ -8,20 +8,25 @@ inherit external-toolchain
 
 PACKAGES =+ "libgcov-dev"
 
+external_libroot = "${@os.path.realpath('${EXTERNAL_TOOLCHAIN_LIBROOT}').replace(os.path.realpath('${EXTERNAL_TOOLCHAIN}') + '/', '/')}"
+FILES_MIRRORS =. "${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/|${external_libroot}/\n"
+
 FILES_${PN} = "${base_libdir}/libgcc_s.so.*"
 FILES_${PN}-dev = "${base_libdir}/libgcc_s.so \
-                   ${libdir}/gcc/${EXTERNAL_TARGET_SYS}/${GCC_VERSION}/crtbegin.o \
-                   ${libdir}/gcc/${EXTERNAL_TARGET_SYS}/${GCC_VERSION}/crtbeginS.o \
-                   ${libdir}/gcc/${EXTERNAL_TARGET_SYS}/${GCC_VERSION}/crtbeginT.o \
-                   ${libdir}/gcc/${EXTERNAL_TARGET_SYS}/${GCC_VERSION}/crtend.o \
-                   ${libdir}/gcc/${EXTERNAL_TARGET_SYS}/${GCC_VERSION}/crtendS.o \
-                   ${libdir}/gcc/${EXTERNAL_TARGET_SYS}/${GCC_VERSION}/crtfastmath.o \
-                   ${libdir}/gcc/${EXTERNAL_TARGET_SYS}/${GCC_VERSION}/crtprec*.o \
-                   ${libdir}/gcc/${EXTERNAL_TARGET_SYS}/${GCC_VERSION}/libgcc.a \
-                   ${libdir}/gcc/${EXTERNAL_TARGET_SYS}/${GCC_VERSION}/libgcc_eh.a"
+                   ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/crtbegin.o \
+                   ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/crtbeginS.o \
+                   ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/crtbeginT.o \
+                   ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/crtend.o \
+                   ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/crtendS.o \
+                   ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/crtfastmath.o \
+                   ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/crtprec*.o \
+                   ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/libgcc.a \
+                   ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/libgcc_eh.a \
+                   ${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/include/unwind.h \
+                   "
 INSANE_SKIP_${PN}-dev += "staticdev"
 FILES_${PN}-dbg += "${base_libdir}/.debug/libgcc_s.so.*.debug"
-FILES_libgcov-dev = "${libdir}/gcc/${EXTERNAL_TARGET_SYS}/${GCC_VERSION}/libgcov.a"
+FILES_libgcov-dev = "${libdir}/gcc/${TARGET_SYS}/${GCC_VERSION}/libgcov.a"
 INSANE_SKIP_libgcov-dev += "staticdev"