[PATCH] lib: fix warnings when building with clang

diff --git a/3e/560c24231ec0b827cd7529c6e00a3d78d38220 b/3e/560c24231ec0b827cd7529c6e00a3d78d38220
new file mode 100644 (file)
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+++ b/3e/560c24231ec0b827cd7529c6e00a3d78d38220
@@ -0,0 +1,119 @@
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+From: Jani Nikula <jani@nikula.org>\r
+To: notmuch@notmuchmail.org\r
+Subject: [PATCH] lib: fix warnings when building with clang\r
+Date: Mon,  1 Oct 2012 09:36:11 +0200\r
+Message-Id: <1349076971-2065-1-git-send-email-jani@nikula.org>\r
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+\r
+Building notmuch with CC=clang and CXX=clang++ produces the warnings:\r
+\r
+CC -O2 lib/tags.o\r
+lib/tags.c:43:5: warning: expression result unused [-Wunused-value]\r
+    talloc_steal (tags, list);\r
+    ^~~~~~~~~~~~~~~~~~~~~~~~~\r
+/usr/include/talloc.h:345:143: note: expanded from:\r
+  ...__location__); __talloc_steal_ret; })\r
+                    ^~~~~~~~~~~~~~~~~~\r
+1 warning generated.\r
+\r
+CXX -O2 lib/message.o\r
+lib/message.cc:791:5: warning: expression result unused [-Wunused-value]\r
+    talloc_reference (message, message->tag_list);\r
+    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\r
+/usr/include/talloc.h:932:36: note: expanded from:\r
+  ...(_TALLOC_TYPEOF(ptr))_talloc_reference_loc((ctx),(ptr), __location__)\r
+     ^                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\r
+1 warning generated.\r
+\r
+Check talloc_reference() return value, and explicitly ignore\r
+talloc_steal() return value as it has no failure modes, to silence the\r
+warnings.\r
+---\r
+ lib/message.cc |    4 +++-\r
+ lib/tags.c     |    2 +-\r
+ 2 files changed, 4 insertions(+), 2 deletions(-)\r
+\r
+diff --git a/lib/message.cc b/lib/message.cc\r
+index 978de06..320901f 100644\r
+--- a/lib/message.cc\r
++++ b/lib/message.cc\r
+@@ -788,7 +788,9 @@ notmuch_message_get_tags (notmuch_message_t *message)\r
+      * possible to modify the message tags (which talloc_unlink's the\r
+      * current list from the message) while still iterating because\r
+      * the iterator will keep the current list alive. */\r
+-    talloc_reference (message, message->tag_list);\r
++    if (!talloc_reference (message, message->tag_list))\r
++      return NULL;\r
++\r
+     return tags;\r
+ }\r
+ \r
+diff --git a/lib/tags.c b/lib/tags.c\r
+index c58924f..b7e5602 100644\r
+--- a/lib/tags.c\r
++++ b/lib/tags.c\r
+@@ -40,7 +40,7 @@ _notmuch_tags_create (const void *ctx, notmuch_string_list_t *list)\r
+       return NULL;\r
+ \r
+     tags->iterator = list->head;\r
+-    talloc_steal (tags, list);\r
++    (void) talloc_steal (tags, list);\r
+ \r
+     return tags;\r
+ }\r
+-- \r
+1.7.2.5\r
+\r