diff --git a/libc/src/stdio/scanf_core/CMakeLists.txt b/libc/src/stdio/scanf_core/CMakeLists.txt
index ce639fe65a106..e8125ff465020 100644
--- a/libc/src/stdio/scanf_core/CMakeLists.txt
+++ b/libc/src/stdio/scanf_core/CMakeLists.txt
@@ -54,6 +54,12 @@ add_header_library(
     libc.src.__support.CPP.string_view
 )
 
+if(NOT(TARGET libc.src.__support.File.file) AND LLVM_LIBC_FULL_BUILD)
+  # Not all platforms have a file implementation. If file is unvailable, and a
+  # full build is requested, then we must skip all file based scanf sections.
+  return()
+endif()
+
 add_object_library(
   scanf_main
   SRCS
diff --git a/libc/test/src/stdio/scanf_core/CMakeLists.txt b/libc/test/src/stdio/scanf_core/CMakeLists.txt
index 9cdc6547821ee..9d05c7d4b89d1 100644
--- a/libc/test/src/stdio/scanf_core/CMakeLists.txt
+++ b/libc/test/src/stdio/scanf_core/CMakeLists.txt
@@ -18,6 +18,12 @@ add_libc_unittest(
     libc.src.__support.arg_list
 )
 
+if(NOT(TARGET libc.src.__support.File.file) AND LLVM_LIBC_FULL_BUILD)
+  # Not all platforms have a file implementation. If file is unvailable, and a
+  # full build is requested, then we must skip all file based scanf sections.
+  return()
+endif()
+
 add_libc_unittest(
   reader_test
   SUITE