[PATCH] Compilation: zero-length array declaration.

ISO C99 (and GCC 3.x or later) lets you write a flexible array
at the end of a structure, like this:

	struct frotz {
		int xyzzy;
		char nitfol[]; /* more */
	};

GCC 2.95 and 2.96 let you to do this with "char nitfol[0]";
unfortunately this is not allowed by ISO C90.

This declares such construct like this:

	struct frotz {
		int xyzzy;
		char nitfol[FLEX_ARRAY]; /* more */
	};

and git-compat-util.h defines FLEX_ARRAY to 0 for gcc 2.95 and
empty for others.

If you are using a C90 C compiler, you should be able
to override this with CFLAGS=-DFLEX_ARRAY=1 from the
command line of "make".

Signed-off-by: Junio C Hamano <junkio@cox.net>

10 files changed, 21 insertions, 12 deletions

diff --git a/blob.c b/blob.c
index ea52ad5c9d..84ec1212e7 100644
--- a/blob.c
+++ b/blob.c
@@ -1,5 +1,5 @@
-#include "blob.h"
 #include "cache.h"
+#include "blob.h"
 #include <stdlib.h>
 
 const char *blob_type = "blob";
diff --git a/cache.h b/cache.h
index cb87becb3a..5fd2687636 100644
--- a/cache.h
+++ b/cache.h
@@ -81,7 +81,7 @@ struct cache_entry {
 	unsigned int ce_size;
 	unsigned char sha1[20];
 	unsigned short ce_flags;
-	char name[0];
+	char name[FLEX_ARRAY]; /* more */
 };
 
 #define CE_NAMEMASK  (0x0fff)
@@ -257,7 +257,7 @@ extern int checkout_entry(struct cache_entry *ce, struct checkout *state);
 extern struct alternate_object_database {
 	struct alternate_object_database *next;
 	char *name;
-	char base[0]; /* more */
+	char base[FLEX_ARRAY]; /* more */
 } *alt_odb_list;
 extern void prepare_alt_odb(void);
 
@@ -271,7 +271,8 @@ extern struct packed_git {
 	unsigned int pack_use_cnt;
 	int pack_local;
 	unsigned char sha1[20];
-	char pack_name[0]; /* something like ".git/objects/pack/xxxxx.pack" */
+	/* something like ".git/objects/pack/xxxxx.pack" */
+	char pack_name[FLEX_ARRAY]; /* more */
 } *packed_git;
 
 struct pack_entry {
@@ -286,7 +287,7 @@ struct ref {
 	unsigned char new_sha1[20];
 	unsigned char force;
 	struct ref *peer_ref; /* when renaming */
-	char name[0];
+	char name[FLEX_ARRAY]; /* more */
 };
 
 extern int git_connect(int fd[2], char *url, const char *prog);
diff --git a/commit.c b/commit.c
index edd4dedcdd..fb02ba609b 100644
--- a/commit.c
+++ b/commit.c
@@ -1,6 +1,6 @@
+#include "cache.h"
 #include "tag.h"
 #include "commit.h"
-#include "cache.h"
 
 int save_commit_buffer = 1;
 
diff --git a/git-compat-util.h b/git-compat-util.h
index c353b276f0..12ce6590bb 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1,6 +1,14 @@
 #ifndef GIT_COMPAT_UTIL_H
 #define GIT_COMPAT_UTIL_H
 
+#ifndef FLEX_ARRAY
+#if defined(__GNUC__) && (__GNUC__ < 3)
+#define FLEX_ARRAY 0
+#else
+#define FLEX_ARRAY /* empty */
+#endif
+#endif
+
 #include <unistd.h>
 #include <stdio.h>
 #include <sys/stat.h>
diff --git a/ls-files.c b/ls-files.c
index cd87430127..74ec8c0aee 100644
--- a/ls-files.c
+++ b/ls-files.c
@@ -208,7 +208,7 @@ static int excluded(const char *pathname)
 
 struct nond_on_fs {
 	int len;
-	char name[0];
+	char name[FLEX_ARRAY]; /* more */
 };
 
 static struct nond_on_fs **dir;
diff --git a/object.c b/object.c
index cf5931a942..1577f74281 100644
--- a/object.c
+++ b/object.c
@@ -1,8 +1,8 @@
+#include "cache.h"
 #include "object.h"
 #include "blob.h"
 #include "tree.h"
 #include "commit.h"
-#include "cache.h"
 #include "tag.h"
 
 struct object **objs;
diff --git a/object.h b/object.h
index 336d986b51..0e7618283c 100644
--- a/object.h
+++ b/object.h
@@ -9,7 +9,7 @@ struct object_list {
 
 struct object_refs {
 	unsigned count;
-	struct object *ref[0];
+	struct object *ref[FLEX_ARRAY]; /* more */
 };
 
 struct object {
diff --git a/receive-pack.c b/receive-pack.c
index 92878ecac3..ce986fe11c 100644
--- a/receive-pack.c
+++ b/receive-pack.c
@@ -24,7 +24,7 @@ struct command {
 	unsigned char updated;
 	unsigned char old_sha1[20];
 	unsigned char new_sha1[20];
-	char ref_name[0];
+	char ref_name[FLEX_ARRAY]; /* more */
 };
 
 static struct command *commands = NULL;
diff --git a/tag.c b/tag.c
index 61ac434d6b..ac0e57398a 100644
--- a/tag.c
+++ b/tag.c
@@ -1,5 +1,5 @@
-#include "tag.h"
 #include "cache.h"
+#include "tag.h"
 
 const char *tag_type = "tag";
 
diff --git a/tree.c b/tree.c
index e7a7b7190c..dc1c41e938 100644
--- a/tree.c
+++ b/tree.c
@@ -1,8 +1,8 @@
+#include "cache.h"
 #include "tree.h"
 #include "blob.h"
 #include "commit.h"
 #include "tag.h"
-#include "cache.h"
 #include <stdlib.h>
 
 const char *tree_type = "tree";