commit-reach.h: add missing declarations (hdr-check)

ramsay-jones · gitster · commit 1406725b8819 · 2018-10-29T10:14:21.000+09:00
Add the necessary #includes and forward declarations to allow the header file to pass the 'hdr-check' target. Note that, since this header includes the commit-slab implementation header file (indirectly via commit-slab.h), some of the commit-slab inline functions (e.g contains_cache_at_peek()) will not compile without the complete type of 'struct commit'. Hence, we replace the forward declaration of 'struct commit' with the an #include of the 'commit.h' header file. It is possible, using the 'commit-slab-{decl,impl}.h' files, to avoid this inclusion of the 'commit.h' header. Commit a9f1f1f ("commit-slab.h: code split", 2018-05-19) separated the commit-slab interface from its implementation, to allow for the definition of a public commit-slab data structure. This enabled us to avoid including the commit-slab implementation in a header file, which could result in the replication of the commit-slab functions in each compilation unit in which it was included. Indeed, if you compile with optimizations disabled, then run this script: $ cat -n dup-static.sh 1 #!/bin/sh 2 3 nm $1 | grep ' t ' | cut -d' ' -f3 | sort | uniq -c | 4 sort -rn | grep -v ' 1' $ $ ./dup-static.sh git | grep contains 24 init_contains_cache_with_stride 24 init_contains_cache 24 contains_cache_peek 24 contains_cache_at_peek 24 contains_cache_at 24 clear_contains_cache $ you will find 24 copies of the commit-slab routines for the contains_cache. Of course, when you enable optimizations again, these duplicate static functions (mostly) disappear. Compiling with gcc at -O2, leaves two static functions, thus: $ nm commit-reach.o | grep contains_cache 0000000000000870 t contains_cache_at_peek.isra.1.constprop.6 $ nm ref-filter.o | grep contains_cache 00000000000002b0 t clear_contains_cache.isra.14 $ However, using a shared 'contains_cache' would result in all six of the above functions as external public functions in the git binary. At present, only three of these functions are actually called, so the trade-off seems to favour letting the compiler inline the commit-slab functions. Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/commit-reach.h b/commit-reach.h
@@ -1,12 +1,13 @@
 #ifndef __COMMIT_REACH_H__
 #define __COMMIT_REACH_H__
 
+#include "commit.h"
 #include "commit-slab.h"
 
-struct commit;
 struct commit_list;
-struct contains_cache;
 struct ref_filter;
+struct object_id;
+struct object_array;
 
 struct commit_list *get_merge_bases_many(struct commit *one,
 					 int n,
