WIP: github: Use a nightly compiler build

This is needed for both openmp and compiler-rt tests.

Author: mstorsjo

.github/workflows/build.yml

@@ -352,7 +352,7 @@ jobs:
             make
       - name: Unpack toolchain
         run: |
-          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/20250417/llvm-mingw-20250417-ucrt-${{matrix.arch}}.zip
+          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/nightly/llvm-mingw-nightly-ucrt-${{matrix.arch}}.zip
           unzip -q llvm-mingw-*.zip
           rm llvm-mingw-*.zip
           mv llvm-mingw-* /llvm-mingw
@@ -391,7 +391,7 @@ jobs:
           choco install ninja
       - name: Unpack toolchain
         run: |
-          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/20250417/llvm-mingw-20250417-ucrt-${{matrix.arch}}.zip
+          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/nightly/llvm-mingw-nightly-ucrt-${{matrix.arch}}.zip
           Expand-Archive llvm-mingw-*.zip -DestinationPath .
           del llvm-mingw-*.zip
           mv llvm-mingw-* c:\llvm-mingw
@@ -451,7 +451,7 @@ jobs:
           choco install ninja
       - name: Unpack toolchain
         run: |
-          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/20250417/llvm-mingw-20250417-ucrt-${{matrix.arch}}.zip
+          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/nightly/llvm-mingw-nightly-ucrt-${{matrix.arch}}.zip
           Expand-Archive llvm-mingw-*.zip -DestinationPath .
           del llvm-mingw-*.zip
           mv llvm-mingw-* c:\llvm-mingw
@@ -515,7 +515,7 @@ jobs:
           choco install ninja
       - name: Unpack toolchain
         run: |
-          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/20250417/llvm-mingw-20250417-ucrt-${{matrix.arch}}.zip
+          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/nightly/llvm-mingw-nightly-ucrt-${{matrix.arch}}.zip
           Expand-Archive llvm-mingw-*.zip -DestinationPath .
           del llvm-mingw-*.zip
           mv llvm-mingw-* c:\llvm-mingw
@@ -652,7 +652,7 @@ jobs:
             nasm:p
       - name: Unpack toolchain
         run: |
-          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/20250417/llvm-mingw-20250417-ucrt-${{matrix.arch}}.zip
+          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/nightly/llvm-mingw-nightly-ucrt-${{matrix.arch}}.zip
           unzip -q llvm-mingw-*.zip
           rm llvm-mingw-*.zip
           mv llvm-mingw-* /llvm-mingw