Martin Storsjö <[email protected]> writes:

> Some msvcrt versions (the static 64 bit libc in MSVC 10) have
> a log2 function, but there is no declaration for it in the headers.
> Therefore, the normal configure check might find it, but it can fail
> during build or at runtime, depending on whether implicit function
> declarations are an error or not.
>
> Therefore simply ignore this function on this platform.
> ---
> This is the deps section where it feels least out of place. Having the
> dep declared in the msvcrt section would feel odd since it (as a
> dependency) can be set unconditionally, not only if we've actually
> detected that libc. (OTOH, in that section it could be a straight
> "disable log2" instead.)

Not without changing the enable in check_mathfunc to enable_weak.

> ---
>
>  configure |    2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/configure b/configure
> index ae8e765..d5809aa 100755
> --- a/configure
> +++ b/configure
> @@ -1381,6 +1381,8 @@ need_memalign="altivec neon sse"
>  
>  symver_if_any="symver_asm_label symver_gnu_asm"
>  
> +log2_deps="!msvcrt"
> +
>  # subsystems
>  dct_select="rdft"
>  mdct_select="fft"
> -- 

LGTM

This is as good a solution as any.

-- 
Måns Rullgård
[email protected]
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