clang,windows: fix passing link flags when using clang in GNU frontend mode on windows

.github/workflows/test.yaml

@@ -61,6 +61,7 @@ jobs:
         compiler:
           - cl
           - clang-cl
+          - clang
         include:
           - os: windows-2022
             vs_version: vs-2022
@@ -79,6 +80,10 @@ jobs:
             arch: i686
           - compiler: clang-cl
             arch: aarch64
+          - compiler: clang
+            arch: i686
+          - compiler: clang
+            arch: aarch64
 
     steps:
       - uses: actions/checkout@v4

CMakePresets.json

@@ -200,6 +200,10 @@
             "name": "ninja-x86_64-pc-windows-msvc-clang-cl",
             "inherits": ["ninja", "x86_64-pc-windows-msvc", "clang-cl"]
         },
+        {
+            "name": "ninja-x86_64-pc-windows-msvc-clang",
+            "inherits": ["ninja", "x86_64-pc-windows-msvc", "clang"]
+        },
         {
             "name": "ninja-i686-pc-windows-msvc-cl",
             "inherits": ["ninja", "i686-pc-windows-msvc", "cl", "windows-10-cross"]
@@ -208,6 +212,10 @@
             "name": "ninja-i686-pc-windows-msvc-clang-cl",
             "inherits": ["ninja", "i686-pc-windows-msvc", "clang-cl", "windows-10-cross"]
         },
+        {
+            "name": "ninja-i686-pc-windows-msvc-clang",
+            "inherits": ["ninja", "i686-pc-windows-msvc", "clang", "windows-10-cross"]
+        },
         {
             "name": "ninja-aarch64-pc-windows-msvc-cl",
             "inherits": ["ninja", "aarch64-pc-windows-msvc", "cl", "windows-10-cross"]
@@ -216,6 +224,10 @@
             "name": "ninja-aarch64-pc-windows-msvc-clang-cl",
             "inherits": ["ninja", "aarch64-pc-windows-msvc", "clang-cl", "windows-10-cross"]
         },
+        {
+            "name": "ninja-aarch64-pc-windows-msvc-clang",
+            "inherits": ["ninja", "aarch64-pc-windows-msvc", "clang", "windows-10-cross"]
+        },
         {
             "name": "ninja-x86_64-pc-windows-gnullvm",
             "inherits": ["ninja", "windows-only", "clang"],

cmake/FindRust.cmake

@@ -184,7 +184,13 @@ function(_corrosion_determine_libs_new target_triple out_libs out_flags)
 
                 # Flags start with / for MSVC
                 if (lib MATCHES "^/" AND ${target_triple} MATCHES "msvc$")
-                    list(APPEND flag_list "${lib}")
+                    # Windows GNU uses the compiler to invoke the linker, so -Wl, prefix is needed
+                    # https://gitlab.kitware.com/cmake/cmake/-/blob/9bed4f4d817f139f0c2e050d7420e1e247949fe4/Modules/Platform/Windows-GNU.cmake#L156
+                    if (CMAKE_CXX_COMPILER_FRONTEND_VARIANT STREQUAL "GNU")
+                        list(APPEND flag_list "-Wl,${lib}")
+                    else()
+                        list(APPEND flag_list "${lib}")
+                    endif()
                 else()
                     # Strip leading `-l` (unix) and potential .lib suffix (windows)
                     string(REGEX REPLACE "^-l" "" "stripped_lib" "${lib}")
@@ -196,7 +202,7 @@ function(_corrosion_determine_libs_new target_triple out_libs out_flags)
             # We leave it up to the C/C++ executable that links in the Rust static-library
             # to determine which version of the msvc runtime library it should select.
             list(FILTER libs_list EXCLUDE REGEX "^msvcrtd?")
-            list(FILTER flag_list EXCLUDE REGEX "^/defaultlib:msvcrtd?")
+            list(FILTER flag_list EXCLUDE REGEX "^(-Wl,)?/defaultlib:msvcrtd?")
         else()
             message(DEBUG "Determining required native libraries - failed: Regex match failure.")
             message(DEBUG "`native-static-libs` not found in: `${cargo_build_error_message}`")