Specify the output file for GNU-style deps

src/dds/build/plan/compile_exec.cpp

                 "file to exist: [{}])",
                 df_path.string());
         } else {
-            auto dep_info           = dds::parse_mkfile_deps_file(df_path);
+            auto dep_info = dds::parse_mkfile_deps_file(df_path);
+            assert(dep_info.output == cf.object_file_path);
             dep_info.command        = quote_command(cf.cmd_info.command);
             dep_info.command_output = compile_res.output;
             ret_deps_info           = std::move(dep_info);

src/dds/toolchain/from_dds.test.cpp

 
 TEST_CASE("Generating toolchain commands") {
     check_tc_compile("Compiler-ID: GNU",
-                     "g++ -fPIC -fdiagnostics-color -pthread -MD -MF foo.o.d -c foo.cpp -ofoo.o",
+                     "g++ -fPIC -fdiagnostics-color -pthread -MD -MF foo.o.d -MT foo.o -c foo.cpp -ofoo.o",
                      "g++ -fPIC -fdiagnostics-color -pthread -Wall -Wextra -Wpedantic -Wconversion "
-                     "-MD -MF foo.o.d -c foo.cpp -ofoo.o",
+                     "-MD -MF foo.o.d -MT foo.o -c foo.cpp -ofoo.o",
                      "ar rcs stuff.a foo.o bar.o",
                      "g++ -fPIC -fdiagnostics-color foo.o bar.a -pthread -lstdc++fs -omeow.exe");
 
     check_tc_compile(
         "Compiler-ID: GNU\nDebug: True",
-        "g++ -g -fPIC -fdiagnostics-color -pthread -MD -MF foo.o.d -c foo.cpp -ofoo.o",
+        "g++ -g -fPIC -fdiagnostics-color -pthread -MD -MF foo.o.d -MT foo.o -c foo.cpp -ofoo.o",
         "g++ -g -fPIC -fdiagnostics-color -pthread -Wall -Wextra -Wpedantic -Wconversion "
-        "-MD -MF foo.o.d -c foo.cpp -ofoo.o",
+        "-MD -MF foo.o.d -MT foo.o -c foo.cpp -ofoo.o",
         "ar rcs stuff.a foo.o bar.o",
         "g++ -fPIC -fdiagnostics-color foo.o bar.a -pthread -lstdc++fs -omeow.exe -g");
 
     check_tc_compile(
         "Compiler-ID: GNU\nDebug: True\nOptimize: True",
-        "g++ -O2 -g -fPIC -fdiagnostics-color -pthread -MD -MF foo.o.d -c foo.cpp -ofoo.o",
+        "g++ -O2 -g -fPIC -fdiagnostics-color -pthread -MD -MF foo.o.d -MT foo.o -c foo.cpp "
+        "-ofoo.o",
         "g++ -O2 -g -fPIC -fdiagnostics-color -pthread -Wall -Wextra -Wpedantic -Wconversion "
-        "-MD -MF foo.o.d -c foo.cpp -ofoo.o",
+        "-MD -MF foo.o.d -MT foo.o -c foo.cpp -ofoo.o",
         "ar rcs stuff.a foo.o bar.o",
         "g++ -fPIC -fdiagnostics-color foo.o bar.a -pthread -lstdc++fs -omeow.exe -O2 -g");
 
                      "lib /nologo /OUT:stuff.a foo.o bar.o",
                      "cl.exe /nologo /EHsc foo.o bar.a /Femeow.exe /MT");
 
-    check_tc_compile("Compiler-ID: MSVC\nDebug: True",
-                     "cl.exe /Z7 /DEBUG /MTd /EHsc /nologo /permissive- /showIncludes /c foo.cpp /Fofoo.o",
-                     "cl.exe /Z7 /DEBUG /MTd /EHsc /nologo /permissive- /W4 /showIncludes /c foo.cpp /Fofoo.o",
-                     "lib /nologo /OUT:stuff.a foo.o bar.o",
-                     "cl.exe /nologo /EHsc foo.o bar.a /Femeow.exe /Z7 /DEBUG /MTd");
+    check_tc_compile(
+        "Compiler-ID: MSVC\nDebug: True",
+        "cl.exe /Z7 /DEBUG /MTd /EHsc /nologo /permissive- /showIncludes /c foo.cpp /Fofoo.o",
+        "cl.exe /Z7 /DEBUG /MTd /EHsc /nologo /permissive- /W4 /showIncludes /c foo.cpp /Fofoo.o",
+        "lib /nologo /OUT:stuff.a foo.o bar.o",
+        "cl.exe /nologo /EHsc foo.o bar.a /Femeow.exe /Z7 /DEBUG /MTd");
 
     auto tc = dds::parse_toolchain_dds(R"(
     Compiler-ID: GNU
                                       "-MD",
                                       "-MF",
                                       "foo.o.d",
+                                      "-MT",
+                                      "foo.o",
                                       "-c",
                                       "foo.cpp",
                                       "-ofoo.o"});
                                       "-MD",
                                       "-MF",
                                       "foo.o.d",
+                                      "-MT",
+                                      "foo.o",
                                       "-c",
                                       "foo.cpp",
                                       "-ofoo.o"});
                                       "-MD",
                                       "-MF",
                                       "foo.o.d",
+                                      "-MT",
+                                      "foo.o",
                                       "-c",
                                       "foo.cpp",
                                       "-ofoo.o"});

src/dds/toolchain/toolchain.cpp

     if (_deps_mode == deps_mode::gnu) {
         gnu_depfile_path = spec.out_path;
         gnu_depfile_path->replace_extension(gnu_depfile_path->extension().string() + ".d");
-        extend(flags, {"-MD"sv, "-MF"sv, std::string_view(gnu_depfile_path->string())});
+        extend(flags,
+               {"-MD"sv,
+                "-MF"sv,
+                std::string_view(gnu_depfile_path->string()),
+                "-MT"sv,
+                std::string_view(spec.out_path.string())});
     } else if (_deps_mode == deps_mode::msvc) {
         flags.push_back("/showIncludes");
     }