docs/releasing: polish LLVM_CONFIG wording/handling

Use consistent way to manage "non-default" llvm installations, clearly
documenting it.

AKA, use LLVM_CONFIG throughout and unset for the Windows/mingw builds.

v2: unset the save_ variable (Andres)

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Andres Gomez <agomez@igalia.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com> (v1)

diff --git a/docs/releasing.html b/docs/releasing.html
index d744115..930de0e 100644 (file)
--- a/docs/releasing.html
+++ b/docs/releasing.html
@@ -437,8 +437,11 @@ Here is one solution that I've been using.
        chmod 755 -fR $__build_root; rm -rf $__build_root
        mkdir -p $__build_root && cd $__build_root
 
-       # For the distcheck, you may want to specify which LLVM to use:
+       # For the native builds - such as distcheck, scons, sanity test, you
+       # may want to specify which LLVM to use:
        # export LLVM_CONFIG=/usr/lib/llvm-3.9/bin/llvm-config
+
+       # Do a full distcheck
        $__mesa_root/autogen.sh && make distcheck
 
        # Build check the tarballs (scons, linux)
@@ -447,22 +450,22 @@ Here is one solution that I've been using.
        cd .. && rm -rf mesa-$__version
 
        # Build check the tarballs (scons, windows/mingw)
-       # You may need to unset LLVM if you set it before:
-       # unset LLVM_CONFIG
+       # Temporary drop LLVM_CONFIG, unless you have a Windows/mingw one.
+       # save_LLVM_CONFIG=`echo $LLVM_CONFIG`; unset LLVM_CONFIG
        tar -xaf mesa-$__version.tar.xz && cd mesa-$__version
        scons platform=windows toolchain=crossmingw
        cd .. && rm -rf mesa-$__version
 
        # Test the automake binaries
        tar -xaf mesa-$__version.tar.xz && cd mesa-$__version
-       # You may want to specify which LLVM to use:
+       # Restore LLVM_CONFIG, if applicable:
+       # export LLVM_CONFIG=`echo $save_LLVM_CONFIG`; unset save_LLVM_CONFIG
        ./configure \
                --with-dri-drivers=i965,swrast \
                --with-gallium-drivers=swrast \
                --with-vulkan-drivers=intel \
                --enable-llvm-shared-libs \
                --enable-llvm \
-               --with-llvm-prefix=/usr/lib/llvm-3.9 \
                --enable-glx-tls \
                --enable-gbm \
                --enable-egl \