[libc] Fix printf config not working (#66834)

The list of printf copts available in config.json wasn't working because
the printf_core subdirectory was included before the printf_copts
variable was defined, making it effectively nothing for the printf
internals. Additionally, the tests weren't respecting the flags so they
would cause the tests to fail. This patch reorders the cmake in src and
adds flag handling in test.

Author: michaelrj-google

libc/src/stdio/CMakeLists.txt

@@ -26,9 +26,6 @@ if(NOT LIBC_TARGET_ARCHITECTURE_IS_GPU)
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/generic)
 endif()
 
-add_subdirectory(printf_core)
-add_subdirectory(scanf_core)
-
 add_entrypoint_object(
   fflush
   SRCS
@@ -286,6 +283,9 @@ add_entrypoint_object(
     ${printf_copts}
 )
 
+add_subdirectory(printf_core)
+add_subdirectory(scanf_core)
+
 add_entrypoint_object(
   ftell
   SRCS

libc/test/src/stdio/CMakeLists.txt

@@ -112,6 +112,16 @@ add_libc_unittest(
     LibcMemoryHelpers
 )
 
+if(LIBC_CONF_PRINTF_DISABLE_FLOAT)
+  list(APPEND sprintf_test_copts "-DLIBC_COPT_PRINTF_DISABLE_FLOAT")
+endif()
+if(LIBC_CONF_PRINTF_DISABLE_INDEX_MODE)
+  list(APPEND sprintf_test_copts "-DLIBC_COPT_PRINTF_DISABLE_INDEX_MODE")
+endif()
+if(LIBC_CONF_PRINTF_DISABLE_WRITE_INT)
+  list(APPEND sprintf_test_copts "-DLIBC_COPT_PRINTF_DISABLE_WRITE_INT")
+endif()
+
 add_fp_unittest(
   sprintf_test
   UNIT_TEST_ONLY
@@ -123,6 +133,8 @@ add_fp_unittest(
     libc.src.stdio.sprintf
     libc.src.__support.FPUtil.fp_bits
     libc.src.__support.FPUtil.platform_defs
+  COMPILE_OPTIONS
+    ${sprintf_test_copts}
 )
 
 add_libc_unittest(