[sql] uClibc doesn't provide malloc_usable_size().

third_party/sqlite/BUILD.gn

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 declare_args() {
   # Controls whether the build should uses the version of sqlite3 library
   # shipped with the system (currently only supported on iOS) or the one
   # shipped with Chromium source.
   use_system_sqlite = is_ios
 }
@@ skipping 18 matching lines @@
         "-Wno-pointer-to-int-cast",
       ]
     }
   }
 
   # "sqlite3" can cause conflicts with the system library.
   component("chromium_sqlite3") {
     visibility = [ ":*" ]
 
     sources = [
+      "amalgamation/config.h",
       "amalgamation/sqlite3.c",
       "amalgamation/sqlite3.h",
     ]
 
     cflags = []
     defines = [
       "SQLITE_ENABLE_FTS3",
 
       # New unicode61 tokenizer with built-in tables.
       "SQLITE_DISABLE_FTS3_UNICODE",
@@ skipping 66 matching lines @@
         "USE_PREAD=1",
       ]
     }
     if (is_linux || is_android) {
       defines += [
         # Linux provides fdatasync(), a faster equivalent of fsync().
         "fdatasync=fdatasync",
       ]
     }
 
-    # SQLite wants to track malloc sizes.  On OSX it uses malloc_size(), on
-    # Windows _msize(), elsewhere it handles it manually by enlarging the malloc
-    # and injecting a field.  Enable malloc_usable_size() for Linux.
-    # NOTE(shess): Android does _not_ export malloc_usable_size().
+    # Pull in config.h on Linux.  This allows use of preprocessor macros which
+    # are not available to the build config.
     if (is_linux) {
-      defines += [
-        "HAVE_MALLOC_H",
-        "HAVE_MALLOC_USABLE_SIZE",
-      ]
+      defines += [ "_HAVE_SQLITE_CONFIG_H" ]
     }
 
     include_dirs = [ "amalgamation" ]
 
     configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [
       "//build/config/compiler:no_chromium_code",
 
       # Must be after no_chromium_code for warning flags to be ordered
       # correctly.
@@ skipping 97 matching lines @@
         "//third_party/icu",
       ]
       if (is_clang) {
         # src/ext/icu/icu.c uses assert(!"string") which causes warnings about
         # conversion from string literal to bool.
         configs -= [ "//build/config/clang:extra_warnings" ]
       }
     }
   }
 }