diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 8b9c311..459d684 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -35,6 +35,7 @@ jobs:
             # test: ${{ fromJson(needs.enumerate-tests.outputs.matrix) }}
             test:
               - test_basic
+              - test_c
         max-parallel: 1
     steps:
       - uses: actions/checkout@v4
@@ -44,9 +45,8 @@ jobs:
           entrypoint: sh
           args: |
             -c "\
-            riscv64-unknown-elf-gcc --version && \
             cd tests/${{ matrix.test }} && \
-            make test.o && \
+            make obj && \
             riscv64-unknown-elf-ld -melf32lriscv -T tb.ld test.o -o tb.elf && \
             riscv64-unknown-elf-objcopy --target=verilog tb.elf tb.hex && \
             echo "done" \
diff --git a/tests/test_basic/Makefile b/tests/test_basic/Makefile
index 0d2d89c..6ceb62f 100644
--- a/tests/test_basic/Makefile
+++ b/tests/test_basic/Makefile
@@ -57,5 +57,7 @@ verify: $(LOGS)
 clean:
 	rm -rf *.vcd *.log *.out *.hex
 
+obj: $(OBJ)
+
 .SECONDARY: %.log %.vcd
-.PHONY: all clean verify
+.PHONY: all clean verify obj
diff --git a/tests/test_c/Makefile b/tests/test_c/Makefile
index d901846..15f1684 100644
--- a/tests/test_c/Makefile
+++ b/tests/test_c/Makefile
@@ -62,6 +62,8 @@ verify: $(LOGS)
 clean:
 	rm -rf *.vcd *.log *.out *.hex
 
-.SECONDARY: %.log %.vcd
-.PHONY: all clean verify
+obj: $(OBJ)
+
+.SECONDARY: %.log %.vcd
+.PHONY: all clean verify obj