diff --git a/libc/seccomp/Android.bp b/libc/seccomp/Android.bp
index a75aa65..b3707bc 100644
--- a/libc/seccomp/Android.bp
+++ b/libc/seccomp/Android.bp
@@ -16,6 +16,7 @@
         "mips64_global_policy.cpp",
     ],
     export_include_dirs: ["include"],
+    cflags: ["-Wall", "-Werror"],
     shared: {
         shared_libs: ["libbase"],
     },
diff --git a/linker/Android.bp b/linker/Android.bp
index 9125fd6..c8c1256 100644
--- a/linker/Android.bp
+++ b/linker/Android.bp
@@ -6,6 +6,7 @@
         "linker_allocator.cpp",
         "linker_memory.cpp",
     ],
+    cflags: ["-Wall", "-Werror"],
 
     // We need to access Bionic private headers in the linker.
     include_dirs: ["bionic/libc"],
diff --git a/tests/libs/Android.bp b/tests/libs/Android.bp
index aa4d0dd..858f2b1 100644
--- a/tests/libs/Android.bp
+++ b/tests/libs/Android.bp
@@ -17,6 +17,10 @@
 cc_defaults {
     name: "bionic_testlib_defaults",
     host_supported: true,
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
     ldflags: [
         "-Wl,--rpath,${ORIGIN}",
         "-Wl,--enable-new-dtags",
diff --git a/tools/relocation_packer/Android.bp b/tools/relocation_packer/Android.bp
index 2907b31..cd6053a 100644
--- a/tools/relocation_packer/Android.bp
+++ b/tools/relocation_packer/Android.bp
@@ -16,11 +16,13 @@
 
 cc_defaults {
     name: "relocation_packer_flags",
-    cppflags: [
+    cflags: [
         "-Wall",
+        "-Werror",
+    ],
+    cppflags: [
         "-Wextra",
         "-Wunused",
-        "-Werror",
         "-Wold-style-cast",
     ],