[libcxx] Enable '-fdelayed-template-parsing' for clang-cl libcxx tests

This patch enables '-fdelayed-template-parsing' in clang-cl based libcxx
tests. This flag was disabled by default in PR#69431, which causes this
test to fail.

Author: zeroomega

libcxx/test/configs/llvm-libc++-shared-clangcl.cfg.in

@@ -5,7 +5,7 @@ lit_config.load_config(config, '@CMAKE_CURRENT_BINARY_DIR@/cmake-bridge.cfg')
 
 config.substitutions.append(('%{flags}', '--driver-mode=g++'))
 config.substitutions.append(('%{compile_flags}',
-    '-fms-runtime-lib=' + config.fms_runtime_lib + ' -nostdinc++ -I %{include} -I %{target-include} -I %{libcxx}/test/support -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_STDIO_ISO_WIDE_SPECIFIERS -DNOMINMAX' + config.dbg_include
+    '-fms-runtime-lib=' + config.fms_runtime_lib + ' -fdelayed-template-parsing' + ' -nostdinc++ -I %{include} -I %{target-include} -I %{libcxx}/test/support -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_STDIO_ISO_WIDE_SPECIFIERS -DNOMINMAX' + config.dbg_include
 ))
 config.substitutions.append(('%{link_flags}',
     '-nostdlib -L %{lib} -lc++ -l' + config.cxx_lib

libcxx/test/configs/llvm-libc++-static-clangcl.cfg.in

@@ -4,8 +4,10 @@
 lit_config.load_config(config, '@CMAKE_CURRENT_BINARY_DIR@/cmake-bridge.cfg')
 
 config.substitutions.append(('%{flags}', '--driver-mode=g++'))
+# clang-cl by default disabled '-fdelayed-template-parsing'. Explicitly enable
+# it here for tests.
 config.substitutions.append(('%{compile_flags}',
-    '-fms-runtime-lib=' + config.fms_runtime_lib + ' -nostdinc++ -I %{include} -I %{target-include} -I %{libcxx}/test/support -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_STDIO_ISO_WIDE_SPECIFIERS -DNOMINMAX' + config.dbg_include
+    '-fms-runtime-lib=' + config.fms_runtime_lib + ' -fdelayed-template-parsing' + ' -nostdinc++ -I %{include} -I %{target-include} -I %{libcxx}/test/support -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_STDIO_ISO_WIDE_SPECIFIERS -DNOMINMAX' + config.dbg_include
 ))
 config.substitutions.append(('%{link_flags}',
     '-nostdlib -L %{lib} -llibc++ -l' + config.cxx_lib