Reduce stack usage of tmpfile(3).

Also ensure that none of our home-grown code uses more than 2KiB per frame.

Change-Id: I8987a17d72f4b7f082bb7fa25e137c8433664c14
diff --git a/libc/Android.mk b/libc/Android.mk
index 2ec1281..b5a8088 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -727,7 +727,10 @@
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES := $(libc_bionic_src_files)
-LOCAL_CFLAGS := $(libc_common_cflags) -Werror
+LOCAL_CFLAGS := $(libc_common_cflags) \
+    -Werror \
+    -Wframe-larger-than=2048 \
+
 LOCAL_CONLYFLAGS := $(libc_common_conlyflags)
 LOCAL_CPPFLAGS := $(libc_common_cppflags)
 LOCAL_C_INCLUDES := $(libc_common_c_includes)