Re: [Qemu-devel] [PATCH 16/16] configure: do_compiler: Dump some extra info under bash

[Thomas Huth]

On 24.04.2018 19:58, Ian Jackson wrote:
> This makes it much easier to find a particular thing in config.log.
> 
> We have to use the ${BASH_LINENO[*]} syntax which is a syntax error in
> other shells, so test what shell we are running and use eval.
> 
> The extra output is only printed if configure is run with bash.  On
> systems where /bin/sh is not bash, it is necessary to say bash
> ./configure to get the extra debug info in the log.
> 
> Suggested-by: Eric Blake <address@hidden>
> Signed-off-by: Ian Jackson <address@hidden>
> CC: Kent R. Spillner <address@hidden>
> CC: Janosch Frank <address@hidden>
> CC: Thomas Huth <address@hidden>
> CC: Peter Maydell <address@hidden>
> CC: Paolo Bonzini <address@hidden>
> ---
> v8: Fix so that it actually works as intended with bash.
> v6: Fix commit message wording.
> v4: No longer tag this patch RFC.
> ---
>  configure | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/configure b/configure
> index aa35aef..f9ba9ea 100755
> --- a/configure
> +++ b/configure
> @@ -60,6 +60,11 @@ do_compiler() {
>      # is compiler binary to execute.
>      local compiler="$1"
>      shift
> +    if test -n "$BASH_VERSION"; then eval '
> +        echo >>config.log "
> +funcs: ${FUNCNAME[*]}
> +lines: ${BASH_LINENO[*]}"
> +    '; fi
>      echo $compiler "$@" >> config.log
>      $compiler "$@" >> config.log 2>&1 || return $?
>      # Test passed. If this is an --enable-werror build, rerun

I just applied the patch and had a look at config.log, and this looks
useful indeed.

Tested-by: Thomas Huth <address@hidden>