measure: icu with PATH set for vcpkg's command only [m3-only] [m3c]

Author: speak-agent

.github/workflows/measure-734.yml

@@ -190,6 +190,8 @@ jobs:
 
       - name: M3 and P3 chain-loaded managed toolset
         continue-on-error: true
+        env:
+          SKIP_M3B: ${{ contains(github.event.head_commit.message, '[m3c]') && '1' || '' }}
         run: |
           set +e +o pipefail
           T="$RUNNER_TEMP/triplets"; mkdir -p "$T"
@@ -220,12 +222,16 @@ jobs:
           }
           setenv "$TOOLS"
           run zlib "M3 managed, CMake port" a
-          run icu  "M3 managed, make port" a
+          [ -n "$SKIP_M3B" ] || run icu  "M3 managed, make port" a
           # The make-based port finds link.exe on PATH; vcpkg keeps the caller's PATH
           # only through VCPKG_KEEP_ENV_VARS.
-          ( export PATH="$TOOLS/bin/Hostx64/x64:$SDK/bin/$SDKVER/x64:/c/Windows/system32:/c/Windows:/c/Windows/System32/Wbem:/c/Windows/System32/WindowsPowerShell/v1.0"
-            export VCPKG_KEEP_ENV_VARS=PATH
-            run icu "M3 managed, make port, toolset first on a kept PATH" k )
+          d="$RUNNER_TEMP/m3-icu-k"; rm -rf "$d"; mkdir -p "$d"
+          printf '{ "name": "m", "version": "0.1.0", "dependencies": ["icu"] }\n' > "$d/vcpkg.json"
+          KP="$(cygpath -w "$TOOLS/bin/Hostx64/x64");$(cygpath -w "$SDK/bin/$SDKVER/x64");C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0"
+          ( cd "$d" && MSYS2_ENV_CONV_EXCL='*' PATH="$KP" VCPKG_KEEP_ENV_VARS=PATH "$V" install --triplet x64-windows-chain --host-triplet x64-windows-chain --overlay-triplets="$(cygpath -w "$T")" ) > m3-icu-k.log 2>&1
+          rc=$?
+          echo "READING M3c: icu with the toolset first on a kept PATH, exit $rc; $(grep -iE 'Restored [0-9]+ package' m3-icu-k.log | head -1)"
+          [ $rc = 0 ] || { grep -iE 'error' m3-icu-k.log | head -8; tail -8 m3-icu-k.log; }
           # P3: the same toolset at another path; a restore means the same ABI hash.
           cp -r "$TOOLS" "$RUNNER_TEMP/tc2"
           setenv "$RUNNER_TEMP/tc2"