diff --git a/src/libc/script.ml b/src/libc/script.ml
index f6b827ab5..01a3789b7 100644
--- a/src/libc/script.ml
+++ b/src/libc/script.ml
@@ -14,8 +14,8 @@ let () =
       let out = Format.sprintf "%s.o" filename in
       let n =
         Format.ksprintf Sys.command
-          "clang -g -O3 -ffreestanding --no-standard-libraries --target=wasm32 \
-           -c -m32 -Iinclude -Wno-int-conversion -Wno-return-type \
+          "clang -O3 -ffreestanding --no-standard-libraries --target=wasm32 -c \
+           -m32 -Iinclude -Wall -Werror -Wno-int-conversion -Wno-return-type \
            -fbracket-depth=512 -DWANT_STRTOD_WITHOUT_LONG_DOUBLE -o %s %s"
           out c_filename
       in
diff --git a/src/libc/src/test-comp.c b/src/libc/src/test-comp.c
index 692edc5f1..15a8c76e2 100644
--- a/src/libc/src/test-comp.c
+++ b/src/libc/src/test-comp.c
@@ -1,19 +1,16 @@
 #include <owi.h>
 
-inline __attribute__((always_inline)) int or_(int a, int b) {
+static __attribute__((naked,noinline,optnone)) _Bool or_(_Bool a, _Bool b) {
   __asm__ __volatile__("local.get 0;"
-                       "i32.const 0;"
-                       "i32.ne;"
                        "local.get 1;"
-                       "i32.const 0;"
-                       "i32.ne;"
                        "i32.or;"
                        "return;");
 }
 
 _Bool __VERIFIER_nondet_bool(void) {
-  _Bool var = owi_i32();
-  owi_assume(or_(var == 0, var == 1));
+  const _Bool var = owi_i32();
+  const _Bool pc = or_(var == 0, var == 1);
+  owi_assume(pc);
   return var;
 }