introduce ZSTD_USE_C90_QSORT

.github/workflows/dev-short-tests.yml

@@ -693,7 +693,7 @@ jobs:
           sudo apt install -y musl-tools
       - name: Compile the project with musl-gcc
         run: |
-          CC=musl-gcc make -j V=1 zstd
+          CC=musl-gcc CPPFLAGS=-DZSTD_USE_C90_QSORT make -j V=1 zstd
 
   intel-cet-compatibility:
     runs-on: ubuntu-latest