gcc: poison default sysroot path

Various pieces of the code assume that the --sysroot option gets passed
into the compiler tools. By having a "sane" default, we don't always
spot when this occurs and this can later show up as breakage in sstate,
or in usage of the external toolchain.

We've long since talked about poisoning the default such that it will
break unless the correct option is specified. This patch does just that.

If this patch causes something to fail to build, it most likely means
the various compiler flags and commands are not correctly being passed
through to the underlying piece of software and that there is a real
problem that needs fixing, its not the fault of this patch.

(From OE-Core rev: 04b725511a505c582a3abdf63d096967f0320779)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-devtools/gcc/gcc-4.9.inc

@@ -122,8 +122,8 @@ EXTRA_OECONF_INTERMEDIATE = "\
 EXTRA_OECONF_append_libc-uclibc = " --disable-decimal-float "
 
 EXTRA_OECONF_PATHS = "\ 
-    --with-gxx-include-dir=${STAGING_DIR_TARGET}${target_includedir}/c++/${BINV} \ 
-    --with-sysroot=${STAGING_DIR_TARGET} \ 
+    --with-gxx-include-dir=/not/exist{target_includedir}/c++/${BINV} \ 
+    --with-sysroot=/not/exist \ 
     --with-build-sysroot=${STAGING_DIR_TARGET} \
 "
 

meta/recipes-devtools/gcc/gcc-cross-canadian.inc

@@ -10,9 +10,9 @@ GCCMULTILIB = "--enable-multilib"
 require gcc-configure-common.inc
 
 EXTRA_OECONF_PATHS = "\
-    --with-gxx-include-dir=${SDKPATH}/sysroots/${TUNE_PKGARCH}${TARGET_VENDOR}-${TARGET_OS}${target_includedir}/c++/${BINV} \
+    --with-gxx-include-dir=/not/exist${target_includedir}/c++/${BINV} \
     --with-build-time-tools=${STAGING_DIR_NATIVE}${prefix_native}/${TARGET_SYS}/bin \
-    --with-sysroot=${SDKPATH}/sysroots/${TUNE_PKGARCH}${TARGET_VENDOR}-${TARGET_OS} \
+    --with-sysroot=/not/exist \
     --with-build-sysroot=${STAGING_DIR_TARGET} \
 "
 # We have to point gcc at a sysroot but we don't need to rebuild if this changes

meta/recipes-devtools/gcc/gcc-cross-initial.inc

@@ -21,7 +21,7 @@ EXTRA_OECONF = "\
     --enable-languages=c \
     ${OPTSPACE} \
     --program-prefix=${TARGET_PREFIX} \
-    --with-sysroot=${STAGING_DIR_TARGET} \
+    --with-sysroot=/not/exist \
     --with-build-sysroot=${GCCCROSS_BUILDSYSROOT} \
     ${EXTRA_OECONF_INITIAL} \
     ${@bb.utils.contains('DISTRO_FEATURES', 'ld-is-gold', '--with-ld=${STAGING_BINDIR_TOOLCHAIN}/${TARGET_PREFIX}ld.bfd', '', d)} \

meta/recipes-devtools/gcc/gcc-cross.inc

@@ -25,8 +25,8 @@ EXTRA_OECONF += "\
 "
 
 EXTRA_OECONF_PATHS = "\
-    --with-gxx-include-dir=${STAGING_DIR_TARGET}${target_includedir}/c++/${BINV} \
-    --with-sysroot=${STAGING_DIR_TARGET} \
+    --with-gxx-include-dir=/not/exist${target_includedir}/c++/${BINV} \
+    --with-sysroot=/not/exist \
     --with-build-sysroot=${STAGING_DIR_TARGET} \
 "
 

meta/recipes-devtools/gcc/gcc-runtime.inc

@@ -4,7 +4,7 @@ CXXFLAGS := "${@oe_filter_out('-fvisibility-inlines-hidden', '${CXXFLAGS}', d)}"
 
 EXTRA_OECONF_PATHS = "\
     --with-gxx-include-dir=${includedir}/c++/${BINV} \
-    --with-sysroot=${STAGING_DIR_TARGET} \
+    --with-sysroot=/not/exist \
     --with-build-sysroot=${STAGING_DIR_TARGET} \
 "
 

meta/recipes-devtools/gcc/libgfortran.inc

@@ -1,7 +1,7 @@
 require gcc-configure-common.inc
 
 EXTRA_OECONF_PATHS = "\
-    --with-sysroot=${STAGING_DIR_TARGET} \
+    --with-sysroot=/not/exist \
     --with-build-sysroot=${STAGING_DIR_TARGET} \
 "