feat: Add support for C++ style forward declares.

In cimple, `struct X;` will now mean the same as `typedef struct X X;`,
which is (roughly) the same behaviour as in C++. This is only to support
having plain `struct X;` declarations where we put our comments vs.
having the typedefs surrounded by ifdefs for C99 reasons (benign typedef
redefinitions are a C11 feature).

.circleci/config.yml

@@ -0,0 +1,19 @@
+---
+version: 2
+
+workflows:
+  version: 2
+  circleci:
+    jobs:
+      - bazel-opt
+
+jobs:
+  bazel-opt:
+    working_directory: /tmp/cirrus-ci-build
+    docker:
+      - image: toxchat/toktok-stack:latest-release
+
+    steps:
+      - checkout
+      - run: /src/workspace/tools/inject-repo hs-cimple
+      - run: cd /src/workspace && bazel test -k //hs-cimple/...

.cirrus.yml

@@ -1,12 +1,12 @@
----
-bazel-opt_task:
-  container:
-    image: toxchat/toktok-stack:latest-release
-    cpu: 2
-    memory: 6G
-  configure_script:
-    - /src/workspace/tools/inject-repo hs-cimple
-  test_all_script:
-    - cd /src/workspace && bazel test -k
-        --config=ci
-        //hs-cimple/...
+# ---
+# bazel-opt_task:
+#   container:
+#     image: toxchat/toktok-stack:latest-release
+#     cpu: 2
+#     memory: 6G
+#   configure_script:
+#     - /src/workspace/tools/inject-repo hs-cimple
+#   test_all_script:
+#     - cd /src/workspace && bazel test -k
+#         --config=ci
+#         //hs-cimple/...

BUILD.bazel

@@ -4,7 +4,10 @@ load("//third_party/haskell/happy:build_defs.bzl", "happy_parser")
 load("//third_party/haskell/hspec-discover:build_defs.bzl", "hspec_test")
 load("//tools/project:build_defs.bzl", "project")
 
-project(license = "gpl3-https")
+project(
+    custom_cirrus = True,
+    license = "gpl3-https",
+)
 
 alex_lexer(
     name = "Lexer",

src/Language/Cimple/Parser.y

@@ -666,6 +666,7 @@ TypedefDecl :: { NonTerm }
 TypedefDecl
 :	typedef QualType ID_SUE_TYPE ';'			{ Fix $ Typedef $2 $3 }
 |	typedef FunctionPrototype(ID_FUNC_TYPE) ';'		{ Fix $ TypedefFunction $2 }
+|	struct ID_SUE_TYPE ';'					{ Fix $ Typedef (Fix (TyStruct $2)) $2 }
 
 QualType :: { NonTerm }
 QualType