Fix CI jobs

Author: mshinwell

.github/workflows/build.yml

@@ -9,19 +9,6 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - name: closure
-            config: --enable-middle-end=closure
-            os: ubuntu-latest
-            build_ocamlparam: ''
-            check_arch: true
-            use_runtime: d
-            ocamlrunparam: "v=0,V=1"
-
-          - name: closure_cfg
-            config: --enable-middle-end=closure --enable-poll-insertion
-            os: ubuntu-latest
-            build_ocamlparam: _,ocamlcfg=1
-
           - name: flambda1
             config: --enable-middle-end=flambda
             os: ubuntu-latest
@@ -92,7 +79,9 @@ jobs:
             check_arch: true
 
           - name: build_upstream_closure
-            config: --enable-middle-end=closure
+            # The --enable-middle-end setting will be ignored (see the
+            # build_upstream rule in the Makefile).
+            config: --enable-middle-end=flambda2
             os: ubuntu-20.04
 
     env:

Makefile

@@ -134,6 +134,7 @@ regen-flambda2-test-dune-rules: $(dune_config_targets)
 build_upstream: ocaml/config.status
 	rsync -a ocaml/ _build_upstream
 	(cd _build_upstream && \
+	    ./configure && \
 	    $(MAKE) world.opt && \
 	    $(MAKE) ocamlnat)