Fix for Windows.

Author: rwgk

.github/workflows/ci_sh_def.yml

@@ -167,7 +167,7 @@ jobs:
         -DDOWNLOAD_CATCH=ON
         -DDOWNLOAD_EIGEN=ON
         -DCMAKE_CXX_STANDARD=17
-        -DCMAKE_CXX_FLAGS="-DPYBIND11_USE_SMART_HOLDER_AS_DEFAULT"
+        -DCMAKE_CXX_FLAGS="-DPYBIND11_USE_SMART_HOLDER_AS_DEFAULT ${{runner.os == 'Windows' && '/GR /EHsc' || ''}}"
         -DPYBIND11_INTERNALS_VERSION=10000000
         "-DPYBIND11_TEST_OVERRIDE=test_call_policies.cpp;test_gil_scoped.cpp;test_thread.cpp"
         ${{ matrix.args }}

.github/workflows/ci_sh_def.yml.patch

@@ -1,5 +1,5 @@
 --- ci.yml	2021-09-20 05:57:17.199789637 -0700
-+++ ci_sh_def.yml	2021-09-20 06:01:17.683813943 -0700
++++ ci_sh_def.yml	2021-09-20 06:45:40.129525604 -0700
 @@ -1,4 +1,16 @@
 -name: CI-SH-AVL
 +# PLEASE KEEP THIS GROUP OF FILES IN SYNC AT ALL TIMES:
@@ -38,7 +38,7 @@
          -DDOWNLOAD_CATCH=ON
          -DDOWNLOAD_EIGEN=ON
          -DCMAKE_CXX_STANDARD=17
-+        -DCMAKE_CXX_FLAGS="-DPYBIND11_USE_SMART_HOLDER_AS_DEFAULT"
++        -DCMAKE_CXX_FLAGS="-DPYBIND11_USE_SMART_HOLDER_AS_DEFAULT ${{runner.os == 'Windows' && '/GR /EHsc' || ''}}"
          -DPYBIND11_INTERNALS_VERSION=10000000
          "-DPYBIND11_TEST_OVERRIDE=test_call_policies.cpp;test_gil_scoped.cpp;test_thread.cpp"
          ${{ matrix.args }}