Add array build by preproc

C/preproc_array/Makefile

@@ -0,0 +1,20 @@
+CPPFLAGS ?= -Werror -Wall -std=c99
+
+program = test
+sources = $(wildcard *.c)
+objects = $(sources:%.c=%.o)
+depends = $(sources:%.c=%.d)
+
+%.d: %.c
+	@$(CPP) $(CPPFLAGS) -c -MP -MM -MT "$@ $*.o" $< >$@
+
+$(program): $(objects)
+	$(CXX) -o $@ $^ $(LDFLAGS) $(LDLIBS)
+
+.PHONY: clean
+clean:
+	rm -f $(program) $(objects) $(depends)
+
+ifneq ($(MAKECMDGOALS),clean)
+-include $(depends)
+endif

C/preproc_array/a.c

@@ -0,0 +1,8 @@
+#include "i.h"
+#include <stdio.h>
+
+static void f1(void) {
+   printf("A\n");
+}
+
+ADD_FUNC(f1);

C/preproc_array/b.c

@@ -0,0 +1,8 @@
+#include "i.h"
+#include <stdio.h>
+
+static void f1(void) {
+   printf("B\n");
+}
+
+ADD_FUNC(f1);

C/preproc_array/i.h

@@ -0,0 +1,11 @@
+typedef void (*my_func_cb)(void);
+
+typedef struct func_ptr_s {
+	my_func_cb cb; /* function callback */
+} func_ptr_t;
+
+#define ADD_FUNC(func_cb)                        \
+	static func_ptr_t ptr_##func_cb              \
+__attribute((used, section("my_array"))) = { \
+	.cb = func_cb,                           \
+}

C/preproc_array/main.c

@@ -0,0 +1,31 @@
+#include "i.h"
+#include <stdio.h>
+
+static void f3(void) {
+	printf("MAIN\n");
+}
+
+ADD_FUNC(f3);   
+
+#define section_foreach_entry(section_name, type_t, elem)    \
+	for (type_t *elem =                                      \
+	     ({                                                \
+	      extern type_t __start_##section_name;         \
+	      &__start_##section_name;                      \
+	      });                                               \
+	     elem !=                                           \
+	     ({                                                \
+	      extern type_t __stop_##section_name;          \
+	      &__stop_##section_name;                       \
+	      });                                               \
+	     ++elem)
+
+
+int main(int argc, char *argv[])
+{
+	section_foreach_entry(my_array, func_ptr_t, entry) {
+		entry->cb(); /* this will call f1, f2 and f3 */
+	}
+
+	return 0;
+}