diff --git a/src/tests.rs b/src/tests.rs
index 9cc6c8d..67b17d0 100644
--- a/src/tests.rs
+++ b/src/tests.rs
@@ -128,7 +128,6 @@ pub fn test_irgen(path: &Path) {
         .args(&[
             "-fsanitize=undefined",
             "-fno-sanitize-recover=all",
-            "-O1",
             &file_path,
             "-o",
             &bin_path,
@@ -396,7 +395,6 @@ pub fn test_end_to_end(path: &Path) {
         .args(&[
             "-fsanitize=undefined",
             "-fno-sanitize-recover=all",
-            "-O1",
             &file_path,
             "-o",
             &bin_path,
diff --git a/tests/reduce-criteria-template.sh b/tests/reduce-criteria-template.sh
index add7baf..8da9ba7 100644
--- a/tests/reduce-criteria-template.sh
+++ b/tests/reduce-criteria-template.sh
@@ -14,7 +14,7 @@ fi
 
 if
   [ $FUZZ_ARG = '-i' ] &&\
-  (! clang -pedantic -Wall -Werror=strict-prototypes -O1 -c test_reduced.c  > out.txt 2>&1 ||\
+  (! clang -pedantic -Wall -Werror=strict-prototypes -c test_reduced.c  > out.txt 2>&1 ||\
   grep 'main-return-type' out.txt ||\
   grep 'conversions than data arguments' out.txt ||\
   grep 'int-conversion' out.txt ||\
@@ -37,7 +37,7 @@ if
   grep 'declaration does not declare anything' out.txt ||\
   grep 'not equal to a null pointer is always true' out.txt ||\
   grep 'empty struct is a GNU extension' out.txt ||\
-  ! gcc -Wall -Wextra -O2 test_reduced.c > outa.txt 2>&1 ||\
+  ! gcc -Wall -Wextra test_reduced.c > outa.txt 2>&1 ||\
   grep 'uninitialized' outa.txt ||\
   grep 'without a cast' outa.txt ||\
   grep 'control reaches end' outa.txt ||\