On 03/22/2013 12:27 PM, Bernhard Walle wrote:
> On Gentoo, the host compiler can only be executed if basename(argv[0])
> is 'gcc' (or 'g++' etc.), not if it's 'gcc.real'. Then it invokes
> gcc-config and fails:
> 
>  | % ln -s /usr/bin/gcc gcc.real
>  | % ./gcc.real --version
>  |
>  |  * gcc-config: Could not get portage CHOST!
>  |  * gcc-config: You should verify that CHOST is set in one of these places:
>  |  * gcc-config:  - //etc/portage/make.conf
>  |  * gcc-config:  - active environment
>  | gcc-config: error: could not get compiler binary path: No such file or directory
> 
> I'm not a Gentoo expert (I'm just forced to use it for that purpose ;-)),
> so I cannot explain further details.
> 
> This patch makes ptxdist working on Gentoo by changing the symbolic link
> from <name>.real to real/<name>, i.e. moving the final toolchain symlink
> to some other directory, keeping the basename.
> 
> It only changes that for the host compiler since a (usually manually
> built) cross-compiler doesn't have that problem.
> 
> Signed-off-by: Bernhard Walle <bernhard@bwalle.de>
> ---
>  bin/ptxdist                   | 5 +++--
>  scripts/wrapper/libwrapper.sh | 9 ++++++++-
>  2 files changed, 11 insertions(+), 3 deletions(-)
> 
> diff --git a/bin/ptxdist b/bin/ptxdist
> index 95382e6..a6317bf 100755
> --- a/bin/ptxdist
> +++ b/bin/ptxdist
> @@ -588,12 +588,13 @@ check_compiler() {
>  			;;
>  		esac
>  
> -		ln -sf "${cc_abs}" "${PTX_WRAPPER_DIR}/${cc_default}.real" &&
> +		[ -d "${PTX_WRAPPER_DIR}/real" ] || mkdir "${PTX_WRAPPER_DIR}/real"
> +		ln -sf "${cc_abs}" "${PTX_WRAPPER_DIR}/real/${cc_default}" &&
>  		ln -sf "${SCRIPTSDIR}/wrapper/host-${cc_default}-wrapper" "${PTX_WRAPPER_DIR}/${cc_default}" &&
>  
>  		if [ -n "${cc_alternate}" ]; then
>  		    ln -sf "${cc_default}" "${PTX_WRAPPER_DIR}/${cc_alternate}" &&
> -		    ln -sf "${cc_default}.real" "${PTX_WRAPPER_DIR}/${cc_alternate}.real"
> +		    ln -sf "${cc_default}" "${PTX_WRAPPER_DIR}/real/${cc_alternate}"
>  		fi || \
>  		    ptxd_bailout "unable to create compiler wrapper link"
>  	done
> diff --git a/scripts/wrapper/libwrapper.sh b/scripts/wrapper/libwrapper.sh
> index f376f7f..adf2f08 100644
> --- a/scripts/wrapper/libwrapper.sh
> +++ b/scripts/wrapper/libwrapper.sh
> @@ -21,10 +21,17 @@ fi
>  . ${PTXDIST_PLATFORMCONFIG}
>  
>  wrapper_exec() {
> +	local compiler_link
>  	if [ "${PTXDIST_VERBOSE}" = 1 -a -n "${PTXDIST_FD_LOGFILE}" ]; then
>  		echo "wrapper: ${PTXDIST_CCACHE} ${0##*/} ${ARG_LIST} $* ${LATE_ARG_LIST}" >&${PTXDIST_FD_LOGFILE}
>  	fi
> -	exec ${PTXDIST_CCACHE} $0.real ${ARG_LIST} "$@" ${LATE_ARG_LIST}
> +	for c in $0.real "$(dirname $0)/real/$(basename $0)" ; do
> +		if [ -x "$c" ] ; then
> +			compiler_link="$c"
> +			break
> +		fi
> +	done

We don't want to have this loop in the hot path. Iff we agree on the
real/X instead of X.real solution, then you should convert all (host and
cross) to use real/X

Marc
> +	exec ${PTXDIST_CCACHE} "$compiler_link" ${ARG_LIST} "$@" ${LATE_ARG_LIST}
>  }
>  
>  cc_check_args() {
> 


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