Re: [PATCH RFC 10/11] configure: Add --disable-demangle

[Mark Wielaard <mark@klomp.org>]

Hi Ilya,

On Mon, 2023-02-06 at 23:25 +0100, Ilya Leoshkevich via Elfutils-devel
wrote:
> __cxa_demangle is normally implemented in the C++ runtime library,
> instrumenting which for MSan is a hassle. Add a knob for disabling it.
> 
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>  configure.ac | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/configure.ac b/configure.ac
> index 7dc9be63..6a5c38af 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -466,11 +466,17 @@ CFLAGS="$CFLAGS -D_GNU_SOURCE"
>  AC_FUNC_STRERROR_R()
>  CFLAGS="$old_CFLAGS"
>  
> +AC_ARG_ENABLE([demangler],
> +AS_HELP_STRING([--disable-demangle],
> +               [Disable libstdc++ demangle support]))

Typo [--disable-demangler] (missing r).
Also we want to enable demangler support by default if the enable
option isn't given, so you need to add [], [enable_demangler=yes] at
the end.

AC_ARG_ENABLE (feature, help-string, [action-if-given], [action-if-not-
given])

So the action-if-not-given is to enable the feature.

Note that otherwise the summary at the end will have nothing for:

    libstdc++ demangle support         : 

Should be either yes or no, even when --enable-demangler or --disable-
demangler isn't given.

Cheers,

Mark

> +AS_IF([test "x$enable_demangler" == xyes],
>  AC_CHECK_LIB([stdc++], [__cxa_demangle], [dnl
>  AC_DEFINE([USE_DEMANGLE], [1], [Defined if demangling is enabled])])
>  AM_CONDITIONAL(DEMANGLE, test "x$ac_cv_lib_stdcpp___cxa_demangle" = "xyes")
>  AS_IF([test "x$ac_cv_lib_stdcpp___cxa_demangle" = "xyes"],
> -      [enable_demangler=yes],[enable_demangler=no])
> +      [enable_demangler=yes],[enable_demangler=no]),
> +AM_CONDITIONAL(DEMANGLE, false))
>  
>  AC_ARG_ENABLE([textrelcheck],
>  AS_HELP_STRING([--disable-textrelcheck],