On Thu, 2024-06-13 at 17:23 +0200, Michał Górny wrote:
> Add a helper function to check whether time_t is 64-bit.  This could
> be used e.g. to deselect tests that rely on timestamps exceeding Y2k38.
> It is meant to be more future-proof than hardcoding a list of 32-bit
> architectures, given the necessity of switching to 64-bit time_t
> in the future.
> 
> Signed-off-by: Michał Górny <mgorny@gentoo.org>
> ---
>  eclass/toolchain-funcs.eclass | 12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
> 
> Pull-Request: https://github.com/gentoo/gentoo/pull/37142
> 
> diff --git a/eclass/toolchain-funcs.eclass b/eclass/toolchain-funcs.eclass
> index cde84e6f34c8..3e20e956e9c2 100644
> --- a/eclass/toolchain-funcs.eclass
> +++ b/eclass/toolchain-funcs.eclass
> @@ -1,4 +1,4 @@
> -# Copyright 2002-2023 Gentoo Authors
> +# Copyright 2002-2024 Gentoo Authors
>  # Distributed under the terms of the GNU General Public License v2
>  
>  # @ECLASS: toolchain-funcs.eclass
> @@ -1251,4 +1251,14 @@ tc-is-lto() {
>  	return 1
>  }
>  
> +# @FUNCTION: tc-has-64bit-time_t
> +# @RETURN: Shell true if time_t is at least 64 bits long, false otherwise
> +tc-has-64bit-time_t() {
> +	"$(tc-getCC)" ${CFLAGS} ${CPPFLAGS} -c -x c - -o /dev/null <<-EOF &>/dev/null
> +		#include <sys/types.h>
> +		int test[sizeof(time_t) >= 8 ? 1 : -1];
> +	EOF
> +	return $?
> +}
> +
>  fi

I take it this can't be done with tc-cpp-is-true because you need more than
just the preprocessor?

Please don't quote $(tc-getCC), CC can have additional arguments in some
cases. We don't quote $(tc-getTARGET_CPP) in tc-cpp-is-true.