[libc] Also add -Wno-pedantic when building with clang. (llvm#112286)

Author: lntue

libc/cmake/modules/LLVMLibCCompileOptionRules.cmake

@@ -155,11 +155,11 @@ function(_get_common_compile_options output_var flags)
     # Silence this warning because _Complex is a part of C99.
     if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
       list(APPEND compile_options "-fext-numeric-literals")
-      list(APPEND compile_options "-Wno-pedantic")
     else()
       list(APPEND compile_options "-Wno-c99-extensions")
       list(APPEND compile_options "-Wno-gnu-imaginary-constant")
     endif()
+    list(APPEND compile_options "-Wno-pedantic")
     list(APPEND compile_options "-Wimplicit-fallthrough")
     list(APPEND compile_options "-Wwrite-strings")
     list(APPEND compile_options "-Wextra-semi")
@@ -239,12 +239,12 @@ function(_get_common_test_compile_options output_var c_test flags)
     if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
       if(NOT c_test)
         list(APPEND compile_options "-fext-numeric-literals")
-        list(APPEND compile_options "-Wno-pedantic")
       endif()
     else()
       list(APPEND compile_options "-Wno-c99-extensions")
       list(APPEND compile_options "-Wno-gnu-imaginary-constant")
     endif()
+    list(APPEND compile_options "-Wno-pedantic")
     # if(NOT CMAKE_COMPILER_IS_GNUCXX)
     #   list(APPEND compile_options "-Wnewline-eof")
     #   list(APPEND compile_options "-Wnonportable-system-include-path")