From b398375a7001accf9534021ac97029f5c620a048 Mon Sep 17 00:00:00 2001
From: "P. Oscar Boykin" <johnynek@users.noreply.github.com>
Date: Mon, 9 Dec 2024 09:00:04 -1000
Subject: [PATCH] boehm gc example (#1301)

* add boehm gc program compiling example

* add file

* update Makefile

* try to build the boehm example in CI

* install package

* try to fix package

* unify make file

* fix -l arg
---
 .github/workflows/ci.yml  |  5 ++++-
 c_runtime/Makefile        | 20 +++++++++++++++++++-
 c_runtime/boehm_example.c | 19 +++++++++++++++++++
 3 files changed, 42 insertions(+), 2 deletions(-)
 create mode 100644 c_runtime/boehm_example.c

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0b116e814..dedb84b66 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -118,12 +118,15 @@ jobs:
           - '8'
     steps:
       - uses: "actions/checkout@v2.1.0"
+      - name: "install boehm"
+        run: "sudo apt-get update && sudo apt install -y libgc1 libgc-dev"
       - name: "test runtime code"
         run: |
           cd c_runtime
           rm -f test_exe
           make && git diff --quiet || { git diff; false; }
-          ./test_exe && cd ..
+          make boehm_example
+          ./test_exe && ./boehm_example && cd ..
       - name: "build assembly"
         run: "sbt \"++${{matrix.scala}}; cli/assembly\""
       - name: "generate c code"
diff --git a/c_runtime/Makefile b/c_runtime/Makefile
index d36d6a353..158305aca 100644
--- a/c_runtime/Makefile
+++ b/c_runtime/Makefile
@@ -1,3 +1,18 @@
+OS := $(shell uname)
+
+# Platform-specific settings
+ifneq ($(wildcard /opt/homebrew/Cellar/bdw-gc),)  # Check if the directory exists
+    LATEST_VERSION := $(shell ls -v /opt/homebrew/Cellar/bdw-gc | tail -n 1)
+    BOEHM_GC := /opt/homebrew/Cellar/bdw-gc/$(LATEST_VERSION)
+endif
+
+ifeq ($(OS), Darwin)
+    CFLAGS += -I$(BOEHM_GC)/include
+    LIBS += "$(BOEHM_GC)/lib/libgc.a"
+else ifeq ($(OS), Linux)
+    LIBS += -lgc
+endif
+
 all: bosatsu_runtime.o test_out bosatsu_ext_Bosatsu_l_Predef.o bosatsu_ext_Bosatsu_l_Prog.o
 
 bosatsu_generated.h: typegen.py
@@ -21,4 +36,7 @@ bosatsu_ext_Bosatsu_l_Predef.o: bosatsu_ext_Bosatsu_l_Predef.c bosatsu_runtime.o
 	gcc -Wall -Werror -c bosatsu_ext_Bosatsu_l_Predef.c
 
 bosatsu_ext_Bosatsu_l_Prog.o: bosatsu_ext_Bosatsu_l_Prog.c bosatsu_runtime.o
-	gcc -Wall -Werror -c bosatsu_ext_Bosatsu_l_Prog.c
\ No newline at end of file
+	gcc -Wall -Werror -c bosatsu_ext_Bosatsu_l_Prog.c
+
+boehm_example: boehm_example.c
+	gcc $(CFLAGS) boehm_example.c $(LIBS) -o boehm_example
\ No newline at end of file
diff --git a/c_runtime/boehm_example.c b/c_runtime/boehm_example.c
new file mode 100644
index 000000000..d365fc68f
--- /dev/null
+++ b/c_runtime/boehm_example.c
@@ -0,0 +1,19 @@
+#include "gc.h"
+#include <assert.h>
+#include <stdio.h>
+
+int main(void) {
+    int i;
+
+    GC_INIT();
+    for (i = 0; i < 10000000; ++i) {
+        int **p = (int **) GC_MALLOC(sizeof(int *));
+        int *q = (int *) GC_MALLOC_ATOMIC(sizeof(int));
+        assert(*p == 0);
+        *p = (int *) GC_REALLOC(q, 2 * sizeof(int));
+        if (i % 100000 == 0)
+            printf("Heap size = %lu bytes\n",
+                   (unsigned long)GC_get_heap_size());
+    }
+    return 0;
+}
\ No newline at end of file