Merge branch 'rj/header-check'

Header files clean-up.

* rj/header-check:
  delta-islands.h: add missing forward declarations (hdr-check)
  midx.h: add missing forward declarations (hdr-check)
  refs/refs-internal.h: add missing declarations (hdr-check)
  refs/packed-backend.h: add missing declaration (hdr-check)
  refs/ref-cache.h: add missing declarations (hdr-check)
  ewah/ewok_rlw.h: add missing include (hdr-check)
  json-writer.h: add missing include (hdr-check)
  Makefile: add a hdr-check target

Makefile

@@ -1796,6 +1796,7 @@ ifndef V
 	QUIET_MSGFMT   = @echo '   ' MSGFMT $@;
 	QUIET_GCOV     = @echo '   ' GCOV $@;
 	QUIET_SP       = @echo '   ' SP $<;
+	QUIET_HDR      = @echo '   ' HDR $<;
 	QUIET_RC       = @echo '   ' RC $@;
 	QUIET_SUBDIR0  = +@subdir=
 	QUIET_SUBDIR1  = ;$(NO_SUBDIR) echo '   ' SUBDIR $$subdir; \
@@ -2678,6 +2679,17 @@ $(SP_OBJ): %.sp: %.c GIT-CFLAGS FORCE
 .PHONY: sparse $(SP_OBJ)
 sparse: $(SP_OBJ)
 
+GEN_HDRS := command-list.h unicode-width.h
+EXCEPT_HDRS := $(GEN_HDRS) compat% xdiff%
+CHK_HDRS = $(filter-out $(EXCEPT_HDRS),$(patsubst ./%,%,$(LIB_H)))
+HCO = $(patsubst %.h,%.hco,$(CHK_HDRS))
+
+$(HCO): %.hco: %.h FORCE
+	$(QUIET_HDR)$(CC) -include git-compat-util.h -I. -o /dev/null -c -xc $<
+
+.PHONY: hdr-check $(HCO)
+hdr-check: $(HCO)
+
 .PHONY: style
 style:
 	git clang-format --style file --diff --extensions c,h

delta-islands.h

@@ -1,6 +1,10 @@
 #ifndef DELTA_ISLANDS_H
 #define DELTA_ISLANDS_H
 
+struct object_id;
+struct packing_data;
+struct commit;
+
 int island_delta_cmp(const struct object_id *a, const struct object_id *b);
 int in_same_island(const struct object_id *, const struct object_id *);
 void resolve_tree_islands(int progress, struct packing_data *to_pack);

ewah/ewok_rlw.h

@@ -19,6 +19,8 @@
 #ifndef __EWOK_RLW_H__
 #define __EWOK_RLW_H__
 
+#include "ewok.h"
+
 #define RLW_RUNNING_BITS (sizeof(eword_t) * 4)
 #define RLW_LITERAL_BITS (sizeof(eword_t) * 8 - 1 - RLW_RUNNING_BITS)
 

json-writer.h

@@ -42,6 +42,8 @@
  * of the given strings.
  */
 
+#include "strbuf.h"
+
 struct json_writer
 {
 	/*

midx.h

@@ -3,6 +3,9 @@
 
 #include "repository.h"
 
+struct object_id;
+struct pack_entry;
+
 struct multi_pack_index {
 	struct multi_pack_index *next;
 

refs/packed-backend.h

@@ -1,6 +1,8 @@
 #ifndef REFS_PACKED_BACKEND_H
 #define REFS_PACKED_BACKEND_H
 
+struct ref_transaction;
+
 /*
  * Support for storing references in a `packed-refs` file.
  *

refs/ref-cache.h

@@ -1,7 +1,10 @@
 #ifndef REFS_REF_CACHE_H
 #define REFS_REF_CACHE_H
 
+#include "cache.h"
+
 struct ref_dir;
+struct ref_store;
 
 /*
  * If this ref_cache is filled lazily, this function is used to load

refs/refs-internal.h

@@ -1,8 +1,12 @@
 #ifndef REFS_REFS_INTERNAL_H
 #define REFS_REFS_INTERNAL_H
 
+#include "cache.h"
+#include "refs.h"
 #include "iterator.h"
 
+struct ref_transaction;
+
 /*
  * Data structures and functions for the internal use of the refs
  * module. Code outside of the refs module should use only the public