[testing] run under strace

Author: the8472

src/ci/docker/host-x86_64/pr-check-2/Dockerfile

@@ -18,6 +18,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   xz-utils \
   libssl-dev \
   pkg-config \
+  strace \
   mingw-w64 \
   && rm -rf /var/lib/apt/lists/*
 
@@ -28,4 +29,5 @@ RUN sh /scripts/sccache.sh
 
 ENV SCRIPT \
         ldd --version && \
-        python3 ../x.py test --stage 1 std -- "write"
+        python3 ../x.py test --stage 1 std -- "write_at" || \
+        strace -ffe write,pwrite,pwrite64,pwritev2 python3 ../x.py test --stage 1 std -- "write_at"