A path to add debug information to mruby memory allocation.

mruby_alloc_debug.patch

diff --git build_config.rb build_config.rb
index 424f9d0..890173a 100644
--- build_config.rb
+++ build_config.rb
@@ -59,7 +59,8 @@ MRuby::Build.new do |conf|
 
 
   # C compiler settings
-  # conf.cc do |cc|
+  conf.cc do |cc|
+    cc.defines << %w(MRB_DEBUG_MALLOC);
   #   cc.command = ENV['CC'] || 'gcc'
   #   cc.flags = [ENV['CFLAGS'] || %w()]
   #   cc.include_paths = ["#{root}/include"]
@@ -67,7 +68,7 @@ MRuby::Build.new do |conf|
   #   cc.option_include_path = '-I%s'
   #   cc.option_define = '-D%s'
   #   cc.compile_options = "%{flags} -MMD -o %{outfile} -c %{infile}"
-  # end
+  end
 
   # Linker settings
   # conf.linker do |linker|
diff --git include/mruby.h include/mruby.h
index 1336d34..450dab0 100644
--- include/mruby.h
+++ include/mruby.h
@@ -41,7 +41,11 @@ typedef int32_t mrb_aspec;
 
 struct mrb_state;
 
+#if defined(MRB_DEBUG_MALLOC)
+typedef void* (*mrb_allocf) (struct mrb_state *, void*, size_t, void *, char const *, int, char const *);
+#else
 typedef void* (*mrb_allocf) (struct mrb_state *mrb, void*, size_t, void *ud);
+#endif
 
 #ifndef MRB_ARENA_SIZE
 #define MRB_ARENA_SIZE 100
@@ -207,11 +211,22 @@ mrb_sym mrb_intern(mrb_state *mrb,const char *cstr)
   return mrb_intern_cstr(mrb, cstr);
 }
 
+#if defined(MRB_DEBUG_MALLOC)
+void *mrb_malloc_debug(mrb_state*, size_t, char const *, int, char const *);
+void *mrb_calloc_debug(mrb_state*, size_t, size_t, char const *, int, char const *);
+void *mrb_realloc_debug(mrb_state*, void*, size_t, char const *, int, char const *);
+void *mrb_free_debug(mrb_state*, void*, char const *, int, char const *);
+#define mrb_malloc(mrb, len)        mrb_malloc_debug((mrb), (len), __FILE__, __LINE__, __func__)
+#define mrb_calloc(mrb, nelem, len) mrb_calloc_debug((mrb), (nelem), (len), __FILE__, __LINE__, __func__)
+#define mrb_realloc(mrb, p, len)    mrb_realloc_debug((mrb), (p), (len), __FILE__, __LINE__, __func__)
+#define mrb_free(mrb, p)            mrb_free_debug((mrb), (p), __FILE__, __LINE__, __func__)
+#else
 void *mrb_malloc(mrb_state*, size_t);
 void *mrb_calloc(mrb_state*, size_t, size_t);
 void *mrb_realloc(mrb_state*, void*, size_t);
-struct RBasic *mrb_obj_alloc(mrb_state*, enum mrb_vtype, struct RClass*);
 void *mrb_free(mrb_state*, void*);
+#endif
+struct RBasic *mrb_obj_alloc(mrb_state*, enum mrb_vtype, struct RClass*);
 
 mrb_value mrb_str_new(mrb_state *mrb, const char *p, size_t len);
 mrb_value mrb_str_new_cstr(mrb_state*, const char*);
diff --git src/gc.c src/gc.c
index 07bc23b..1a3aacb 100644
--- src/gc.c
+++ src/gc.c
@@ -146,16 +146,29 @@ gettimeofday_time(void)
 
 #define GC_STEP_SIZE 1024
 
+#if defined(MRB_DEBUG_MALLOC)
+void*
+mrb_realloc_debug(mrb_state *mrb, void *p, size_t len, char const *file, int line, char const *func)
+#else
 void*
 mrb_realloc(mrb_state *mrb, void *p, size_t len)
+#endif
 {
   void *p2;
 
+#if defined(MRB_DEBUG_MALLOC)
+  p2 = (mrb->allocf)(mrb, p, len, mrb->ud, file ,line, func);
+#else
   p2 = (mrb->allocf)(mrb, p, len, mrb->ud);
+#endif
 
   if (!p2 && len > 0 && mrb->heaps) {
     mrb_garbage_collect(mrb);
+#if defined(MRB_DEBUG_MALLOC)
+    p2 = (mrb->allocf)(mrb, p, len, mrb->ud, file, line, func);
+#else
     p2 = (mrb->allocf)(mrb, p, len, mrb->ud);
+#endif
   }
 
   if (!p2 && len) {
@@ -174,21 +187,38 @@ mrb_realloc(mrb_state *mrb, void *p, size_t len)
   return p2;
 }
 
+#if defined(MRB_DEBUG_MALLOC)
+void*
+mrb_malloc_debug(mrb_state *mrb, size_t len, char const *file, int line, char const *func)
+{
+  return mrb_realloc_debug(mrb, 0, len, file, line, func);
+}
+#else
 void*
 mrb_malloc(mrb_state *mrb, size_t len)
 {
   return mrb_realloc(mrb, 0, len);
 }
+#endif
 
+#if defined(MRB_DEBUG_MALLOC)
+void*
+mrb_calloc_debug(mrb_state *mrb, size_t nelem, size_t len, char const *file, int line, char const *func)
+#else
 void*
 mrb_calloc(mrb_state *mrb, size_t nelem, size_t len)
+#endif
 {
   void *p = NULL;
   size_t size;
 
   if (nelem <= SIZE_MAX / len) {
     size = nelem * len;
+#if defined(MRB_DEBUG_MALLOC)
+    p = mrb_realloc_debug(mrb, 0, size, file, line, func);
+#else
     p = mrb_realloc(mrb, 0, size);
+#endif
 
     if (p && size > 0)
       memset(p, 0, size);
@@ -197,11 +227,19 @@ mrb_calloc(mrb_state *mrb, size_t nelem, size_t len)
   return p;
 }
 
+#if defined(MRB_DEBUG_MALLOC)
+void*
+mrb_free_debug(mrb_state *mrb, void *p, char const *file, int line, char const *func)
+{
+  return (mrb->allocf)(mrb, p, 0, mrb->ud, file, line, func);
+}
+#else
 void*
 mrb_free(mrb_state *mrb, void *p)
 {
   return (mrb->allocf)(mrb, p, 0, mrb->ud);
 }
+#endif
 
 #ifndef MRB_HEAP_PAGE_SIZE
 #define MRB_HEAP_PAGE_SIZE 1024
diff --git src/state.c src/state.c
index adc7da0..0b6c755 100644
--- src/state.c
+++ src/state.c
@@ -25,7 +25,11 @@ mrb_state*
 mrb_open_allocf(mrb_allocf f, void *ud)
 {
   static const mrb_state mrb_state_zero = { 0 };
+#if defined(MRB_DEBUG_MALLOC)
+  mrb_state *mrb = (mrb_state *)(f)(NULL, NULL, sizeof(mrb_state), ud, __FILE__, __LINE__, __func__);
+#else
   mrb_state *mrb = (mrb_state *)(f)(NULL, NULL, sizeof(mrb_state), ud);
+#endif
   if (mrb == NULL) return NULL;
 
   *mrb = mrb_state_zero;
@@ -38,6 +42,40 @@ mrb_open_allocf(mrb_allocf f, void *ud)
   return mrb;
 }
 
+#if defined(MRB_DEBUG_MALLOC)
+static char const *
+filename(char const *path)
+{
+  size_t const len = strlen(path);
+  size_t i;
+  for (i = len - 1; i > 0; --i) {
+    if (path[i] == '/' || path[i] == '\\') {
+      return &path[i+1];
+    }
+  }
+  return path;
+}
+static void*
+allocf(mrb_state *mrb, void *p, size_t size, void *ud, char const *file, int line, char const *func)
+{
+  if (size == 0) {
+    fprintf(stderr, "FREE    : %10p          %15s %4d (%s)\n", p, filename(file), line, func);
+    free(p);
+    return NULL;
+  }
+  else {
+    void *new_ptr = realloc(p, size);
+    if (new_ptr) {
+      if (NULL == p) {
+        fprintf(stderr, "ALLOCATE: %10p %8lu %15s %4d (%s)\n", new_ptr, size, filename(file), line, func);
+      } else {
+        fprintf(stderr, "REALLOC : %10p %8lu %15s %4d (%s)\n", new_ptr, size, filename(file), line, func);
+      }
+    }
+    return new_ptr;
+  }
+}
+#else
 static void*
 allocf(mrb_state *mrb, void *p, size_t size, void *ud)
 {
@@ -49,6 +87,7 @@ allocf(mrb_state *mrb, void *p, size_t size, void *ud)
     return realloc(p, size);
   }
 }
+#endif
 
 struct alloca_header {
   struct alloca_header *next;