try to bugfix win build with less disk usage

.github/workflows/ccpp_win.yml

@@ -6,8 +6,28 @@ on:
       - CI
 
 jobs:
+  build_dep:
+    runs-on: windows-latest
+    
+    steps:
+    - uses: actions/checkout@v1
+    - uses: ilammy/msvc-dev-cmd@v1
+    - name: mkdir in deps
+      run: mkdir deps/build
+    - name: cmake and make deps
+      working-directory: ./deps/build
+      run: |
+        cmake .. -G "Visual Studio 16 2019" -A x64
+        msbuild /m ALL_BUILD.vcxproj
+    - name: Upload artifact
+      uses: actions/upload-artifact@v1.0.0
+      with:
+        name: deps_win
+        path: ./deps/build/destdir/
+
   build:
     runs-on: windows-latest
+    needs: build_dep
     
     steps:
     - uses: actions/checkout@v1
@@ -15,22 +35,22 @@ jobs:
     - name: change date in version
       shell: powershell
       run: (Get-Content version.inc) | Foreach-Object {$_ -replace "\+UNKNOWN", ("_" + [datetime]::Today.ToString("yyyy-MM-dd"))} | Set-Content version.inc
-    - name: mkdir in deps
-      run: mkdir deps/build
-    - name: cmake deps
-      working-directory: ./deps/build
-      run: |
-        cmake .. -G "Visual Studio 16 2019" -A x64
-        msbuild /m ALL_BUILD.vcxproj
-    - name: clean deps
-      working-directory: ./deps/build
-      shell: cmd
-      run: for /d %G in ("./dep_*") do rmdir /S /Q "%~G"
+    - name: mkdir in deps directory
+      run: mkdir deps/destdir
+    - name: download deps
+      uses: actions/download-artifact@v1
+      with:
+        name: deps_win
+        path: deps/destdir
+    - name: echo dir deps
+      run: dir deps
+    - name: echo dir deps destdir
+      run: dir deps/destdir
     - name: mkdir
       run: mkdir build
     - name: cmake
       working-directory: ./build
-      run: cmake .. -G "Visual Studio 16 2019" -A x64 -DCMAKE_PREFIX_PATH="d:\a\Slic3r\Slic3r\deps\build\destdir\usr\local"
+      run: cmake .. -G "Visual Studio 16 2019" -A x64 -DCMAKE_PREFIX_PATH="d:\a\Slic3r\Slic3r\deps\destdir\usr\local"
     - name: make
       working-directory: ./build
       run: msbuild /m /P:Configuration=Release INSTALL.vcxproj

src/libslic3r/utils.cpp

@@ -486,7 +486,7 @@ int check_copy(const std::string &origin, const std::string &copy)
     } while (f1.good() && f2.good());
 
     // All data has been read and compared equal.
-    return (f1.eof() && f2.eof() && fsize == 0) ? 0 : -1;
+    return (f1.eof() && f2.eof() && fsize == std::streampos(0)) ? 0 : -1;
 }
 
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