nixos/testing: remove remaining coverage-data logic

This isn't used anymore as per
https://github.com/NixOS/nixpkgs/pull/72354#discussion_r451031449.

nixos/lib/testing-python.nix

@@ -63,18 +63,12 @@ rec {
           mkdir -p $out
 
           LOGFILE=/dev/null tests='exec(os.environ["testScript"])' ${driver}/bin/nixos-test-driver
-
-          for i in */xchg/coverage-data; do
-            mkdir -p $out/coverage-data
-            mv $i $out/coverage-data/$(dirname $(dirname $i))
-          done
         '';
     };
 
 
   makeTest =
     { testScript
-    , makeCoverageReport ? false
     , enableOCR ? false
     , name ? "unnamed"
     # Skip linting (mainly intended for faster dev cycles)
@@ -153,7 +147,6 @@ rec {
       };
 
       test = passMeta (runTests driver);
-      report = passMeta (releaseTools.gcovReport { coverageRuns = [ test ]; });
 
       nodeNames = builtins.attrNames nodes;
       invalidNodeNames = lib.filter
@@ -169,7 +162,7 @@ rec {
           Please stick to alphanumeric chars and underscores as separation.
         ''
       else
-        (if makeCoverageReport then report else test) // {
+        test // {
           inherit nodes driver test;
         };
 

nixos/modules/testing/test-instrumentation.nix

@@ -74,15 +74,8 @@ with import ../../lib/qemu-flags.nix { inherit pkgs; };
         # OOM killer randomly get rid of processes, since this leads
         # to failures that are hard to diagnose.
         echo 2 > /proc/sys/vm/panic_on_oom
-
-        # Coverage data is written into /tmp/coverage-data.
-        mkdir -p /tmp/xchg/coverage-data
       '';
 
-    # If the kernel has been built with coverage instrumentation, make
-    # it available under /proc/gcov.
-    boot.kernelModules = [ "gcov-proc" ];
-
     # Panic if an error occurs in stage 1 (rather than waiting for
     # user intervention).
     boot.kernelParams =
@@ -111,8 +104,6 @@ with import ../../lib/qemu-flags.nix { inherit pkgs; };
     networking.defaultGateway = mkOverride 150 "";
     networking.nameservers = mkOverride 150 [ ];
 
-    systemd.globalEnvironment.GCOV_PREFIX = "/tmp/xchg/coverage-data";
-
     system.requiredKernelConfig = with config.lib.kernelConfig; [
       (isYes "SERIAL_8250_CONSOLE")
       (isYes "SERIAL_8250")

pkgs/build-support/release/default.nix

@@ -41,10 +41,6 @@ rec {
       doCoverityAnalysis = true;
     } // args);
 
-  gcovReport = args: import ./gcov-report.nix (
-    { inherit runCommand lcov rsync;
-    } // args);
-
   rpmBuild = args: import ./rpm-build.nix (
     { inherit vmTools;
     } // args);

pkgs/build-support/release/gcov-report.nix

@@ -1,49 +0,0 @@
-{ runCommand, lcov, rsync, coverageRuns, lcovFilter ? [ "/nix/store/*" ], baseDirHack ? false }:
-
-runCommand "coverage"
-  { buildInputs = [ lcov rsync ];
-    inherit lcovFilter baseDirHack;
-  }
-  ''
-    mkdir -p $TMPDIR/gcov $out/nix-support $out/coverage
-    info=$out/coverage/full.info
-
-    for p in ${toString coverageRuns}; do
-        if [ -f $p/nix-support/hydra-build-products ]; then
-            cat $p/nix-support/hydra-build-products >> $out/nix-support/hydra-build-products
-        fi
-
-        [ ! -e $p/nix-support/failed ] || touch $out/nix-support/failed
-
-        opts=
-        for d in $p/coverage-data/*; do
-            for i in $(cd $d/nix/store && ls); do
-                if ! [ -e /nix/store/$i/.build ]; then continue; fi
-                if [ -e $TMPDIR/gcov/nix/store/$i ]; then continue; fi
-                echo "copying $i..."
-                rsync -a /nix/store/$i/.build/* $TMPDIR/gcov/
-                if [ -n "$baseDirHack" ]; then
-                    opts="-b $TMPDIR/gcov/$(cd /nix/store/$i/.build && ls)"
-                fi
-            done
-
-            for i in $(cd $d/nix/store && ls); do
-                rsync -a $d/nix/store/$i/.build/* $TMPDIR/gcov/ --include '*/' --include '*.gcda' --exclude '*'
-            done
-        done
-
-        chmod -R u+w $TMPDIR/gcov
-
-        echo "producing info..."
-        geninfo --ignore-errors source,gcov $TMPDIR/gcov --output-file $TMPDIR/app.info $opts
-        cat $TMPDIR/app.info >> $info
-    done
-
-    echo "making report..."
-    set -o noglob
-    lcov --remove $info ''$lcovFilter > $info.tmp
-    set +o noglob
-    mv $info.tmp $info
-    genhtml --show-details $info -o $out/coverage
-    echo "report coverage $out/coverage" >> $out/nix-support/hydra-build-products
-  ''