I'm pretty sure that it's a new feature in the compiler that detects if the
result of a function returning a pointer to a string was saved into
non-constant pointer from const pointer. This seems reasonable and it seems
like consts were misused in those places.
[[[
[39/469] Building C object
CMakeFiles/libsvn_subr.dir/subversion/libsvn_subr/gpg_agent.c.o
/home/tima/dev/svn-trunk/subversion/libsvn_subr/gpg_agent.c: In function
‘find_running_gpg_agent’:
/home/tima/dev/svn-trunk/subversion/libsvn_subr/gpg_agent.c:391:6: warning:
assignment discards ‘const’ qualifier from pointer target type
[-Wdiscarded-qualifiers]
391 | ep = strchr(p, '\n');
| ^
[85/469] Building C object
CMakeFiles/libsvn_subr.dir/subversion/libsvn_subr/subst.c.o
/home/tima/dev/svn-trunk/subversion/libsvn_subr/subst.c: In function
‘build_keywords’:
/home/tima/dev/svn-trunk/subversion/libsvn_subr/subst.c:309:15: warning:
assignment discards ‘const’ qualifier from pointer target type
[-Wdiscarded-qualifiers]
309 | sep = strchr(keyword, '=');
| ^
[93/469] Building C object
CMakeFiles/libsvn_subr.dir/subversion/libsvn_subr/version.c.o
/home/tima/dev/svn-trunk/subversion/libsvn_subr/version.c: In function
‘svn_version__parse_version_string’:
/home/tima/dev/svn-trunk/subversion/libsvn_subr/version.c:257:22: warning:
initialization discards ‘const’ qualifier from pointer target type
[-Wdiscarded-qualifiers]
257 | char *hyphen = strchr(piece, '-');
| ^~~~~~
[144/469] Building C object
CMakeFiles/libsvn_fs_fs.dir/subversion/libsvn_fs_fs/tree.c.o
/home/tima/dev/svn-trunk/subversion/libsvn_fs_fs/tree.c: In function
‘check_newline’:
/home/tima/dev/svn-trunk/subversion/libsvn_fs_fs/tree.c:2488:13: warning:
initialization discards ‘const’ qualifier from pointer target type
[-Wdiscarded-qualifiers]
2488 | char *c = strchr(path, '\n');
| ^~~~~~
[190/469] Building C object
CMakeFiles/libsvn_fs.dir/subversion/libsvn_fs/fs-loader.c.o
/home/tima/dev/svn-trunk/subversion/libsvn_fs/fs-loader.c: In function
‘svn_fs__path_valid’:
/home/tima/dev/svn-trunk/subversion/libsvn_fs/fs-loader.c:493:5: warning:
assignment discards ‘const’ qualifier from pointer target type
[-Wdiscarded-qualifiers]
493 | c = strchr(path, '\n');
| ^
[226/469] Building C object
CMakeFiles/libsvn_diff.dir/subversion/libsvn_diff/parse-diff.c.o
/home/tima/dev/svn-trunk/subversion/libsvn_diff/parse-diff.c: In function
‘git_start’:
/home/tima/dev/svn-trunk/subversion/libsvn_diff/parse-diff.c:1582:19:
warning: assignment discards ‘const’ qualifier from pointer target type
[-Wdiscarded-qualifiers]
1582 | new_path_marker = strstr(old_path_marker, " b/");
| ^
/home/tima/dev/svn-trunk/subversion/libsvn_diff/parse-diff.c:1610:23:
warning: assignment discards ‘const’ qualifier from pointer target type
[-Wdiscarded-qualifiers]
1610 | new_path_marker = strstr(new_path_start, " b/");
| ^
]]]
I prepared a patch that fixes them by adding const where needed. Can anyone
correct me if I'm misunderstanding something?
--
Timofei Zhakov
Index: subversion/libsvn_diff/parse-diff.c
===================================================================
--- subversion/libsvn_diff/parse-diff.c (revision 1932024)
+++ subversion/libsvn_diff/parse-diff.c (working copy)
@@ -1545,12 +1545,12 @@ static svn_error_t *
git_start(enum parse_state *new_state, char *line, svn_patch_t *patch,
apr_pool_t *result_pool, apr_pool_t *scratch_pool)
{
- const char *old_path_start;
+ char *old_path_start;
char *old_path_end;
- const char *new_path_start;
- const char *new_path_end;
+ char *new_path_start;
+ char *new_path_end;
char *new_path_marker;
- const char *old_path_marker;
+ char *old_path_marker;
/* ### Add handling of escaped paths
* http://www.kernel.org/pub/software/scm/git/docs/git-diff.html:
Index: subversion/libsvn_fs/fs-loader.c
===================================================================
--- subversion/libsvn_fs/fs-loader.c (revision 1932024)
+++ subversion/libsvn_fs/fs-loader.c (working copy)
@@ -468,7 +468,7 @@ default_warning_func(void *baton, svn_error_t *err
svn_error_t *
svn_fs__path_valid(const char *path, apr_pool_t *pool)
{
- char *c;
+ const char *c;
/* UTF-8 encoded string without NULs. */
if (! svn_utf__cstring_is_valid(path))
Index: subversion/libsvn_fs_fs/tree.c
===================================================================
--- subversion/libsvn_fs_fs/tree.c (revision 1932024)
+++ subversion/libsvn_fs_fs/tree.c (working copy)
@@ -2485,7 +2485,7 @@ fs_dir_optimal_order(apr_array_header_t **ordered_
static svn_error_t *
check_newline(const char *path, apr_pool_t *pool)
{
- char *c = strchr(path, '\n');
+ const char *c = strchr(path, '\n');
if (c)
return svn_error_createf(SVN_ERR_FS_PATH_SYNTAX, NULL,
Index: subversion/libsvn_subr/gpg_agent.c
===================================================================
--- subversion/libsvn_subr/gpg_agent.c (revision 1932024)
+++ subversion/libsvn_subr/gpg_agent.c (working copy)
@@ -326,7 +326,7 @@ find_running_gpg_agent(int *new_sd, apr_pool_t *po
char *buffer;
const char *socket_name = find_gpg_agent_socket(pool, pool);
const char *request = NULL;
- const char *p = NULL;
+ char *p = NULL;
char *ep = NULL;
int sd;
Index: subversion/libsvn_subr/subst.c
===================================================================
--- subversion/libsvn_subr/subst.c (revision 1932024)
+++ subversion/libsvn_subr/subst.c (working copy)
@@ -298,7 +298,7 @@ build_keywords(apr_hash_t **kw,
for (i = 0; i < keyword_tokens->nelts; ++i)
{
- const char *keyword = APR_ARRAY_IDX(keyword_tokens, i, const char *);
+ char *keyword = APR_ARRAY_IDX(keyword_tokens, i, char *);
const char *custom_fmt = NULL;
if (expand_custom_keywords)
Index: subversion/libsvn_subr/version.c
===================================================================
--- subversion/libsvn_subr/version.c (revision 1932024)
+++ subversion/libsvn_subr/version.c (working copy)
@@ -253,7 +253,7 @@ svn_version__parse_version_string(svn_version_t **
require that it be present. */
if (pieces->nelts == 3)
{
- const char *piece = APR_ARRAY_IDX(pieces, 2, const char *);
+ char *piece = APR_ARRAY_IDX(pieces, 2, char *);
char *hyphen = strchr(piece, '-');
if (hyphen)
{
