[CI] Run Nightly E2E CI in pre-C++11 ABI mode (#16235)

We expect that our runtime library should work with user code compiled
either way, but we don't be running double amount of testing in
pre-commit/post-commit CI to verify that. Nightly looks like a
reasonable choice to test this.

.github/workflows/sycl-nightly.yml

@@ -110,7 +110,7 @@ jobs:
       image_options: ${{ matrix.image_options }}
       target_devices: ${{ matrix.target_devices }}
       tests_selector: ${{ matrix.tests_selector }}
-      extra_lit_opts: ${{ matrix.extra_lit_opts }}
+      extra_lit_opts: "--param 'cxx_flags=-D_GLIBCXX_USE_CXX11_ABI=0' ${{ matrix.extra_lit_opts }}"
       reset_intel_gpu: ${{ matrix.reset_intel_gpu }}
       ref: ${{ github.sha }}
       merge_ref: ''

sycl/test-e2e/lit.site.cfg.py.in

@@ -34,7 +34,7 @@ config.hip_platform = "@HIP_PLATFORM@"
 config.amd_arch = lit_config.params.get("amd_arch", "@AMD_ARCH@")
 config.sycl_threads_lib = '@SYCL_THREADS_LIB@'
 config.extra_environment = lit_config.params.get("extra_environment", "@LIT_EXTRA_ENVIRONMENT@")
-config.cxx_flags = "@SYCL_E2E_CLANG_CXX_FLAGS@"
+config.cxx_flags = lit_config.params.get("cxx_flags", "@SYCL_E2E_CLANG_CXX_FLAGS@")
 config.c_flags = "@CMAKE_C_FLAGS@"
 config.external_tests = "@SYCL_EXTERNAL_TESTS@"
 config.extra_include = "@CMAKE_CURRENT_SOURCE_DIR@/include"