Re: [PATCH 1/2] rust: pick a GCC-compatible Cargo target under MSYS2/MinGW

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi Junio,

On Tue, 1 Sep 2026, Junio C Hamano wrote:

> "Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com>
> writes:
> 
> > +                ifneq (,$(filter %ARM64, $(MSYSTEM)))
> > +			HOST_CPU = aarch64
> > +                else ifneq (,$(filter %32, $(MSYSTEM)))
> > +			HOST_CPU = i686
> > +                else
> > +			HOST_CPU = x86_64
> > +                endif
> > +                ifneq (,$(filter CLANG%, $(MSYSTEM)))
> > +			CARGO_TARGET = $(HOST_CPU)-pc-windows-gnullvm
> > +                else
> > +			CARGO_TARGET = $(HOST_CPU)-pc-windows-gnu
> > +                endif
> 
> Assuming HOST_CPU is x86_64 in the above, as UCRT64, unlike
> CLANG{ARM64,64,32}, does not match CLANG%, I presume that the above
> gives "x86_64-pc-windows-gnu" to builds with MSYSTEM set to UCRT64.

Correct.

> There is this "we only need MINGW64 but the switch to UCRT64 is
> imminent, and others are for documentation" part we see in the
> [PATCH 2/2]
> 
> +        case "$MSYSTEM" in
> +        CLANGARM64) target=aarch64-pc-windows-gnullvm ;;
> +        CLANG64)    target=x86_64-pc-windows-gnullvm  ;;
> +        CLANG32)    target=i686-pc-windows-gnullvm    ;;
> +        UCRT64)     target=x86_64-pc-windows-gnullvm  ;;
> +        MINGW64)    target=x86_64-pc-windows-gnu      ;;
> +        MINGW32)    target=i686-pc-windows-gnu        ;;
> +        *) echo "::error::Unsupported MSYSTEM: $MSYSTEM"; exit 1 ;;
> +        esac &&
> +        rustup target add "$target" &&
> 
> that maps UCRT64 to "x86_64-pc-windows-gnullvm"
> 
> I do not know if it is intended.  If so, please ignore.

Since UCRT64 is still using GCC, it should be `-gnu`. Thanks for catching.

Ciao,
Johannes