Re: [PATCH] don't store temporary value returned from c_str()

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+Date: Sat, 27 Apr 2013 18:05:40 +0200\r
+From: Vladimir Marek <Vladimir.Marek@Oracle.COM>\r
+To: Jani Nikula <jani@nikula.org>\r
+Subject: Re: [PATCH] don't store temporary value returned from c_str()\r
+Message-ID: <20130427160540.GB17459@vi64-x3-2e-prg06.cz.oracle.com>\r
+References: <1366405933-17223-1-git-send-email-Vladimir.Marek@oracle.com>\r
+       <878v44qhop.fsf@nikula.org>\r
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+Cc: notmuch@notmuchmail.org, Vladimir Marek <vlmarek@volny.cz>\r
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+\r
+> It's okay to use the result of .c_str() as long as the string object\r
+> stays in scope, and none of the non-const member functions are\r
+> called. Here, I think the problem is that TermIterator's overloaded\r
+> operator*() returns a string object within the if block's scope, and it\r
+> goes immediately out of scope. You could check this by adding\r
+\r
+Right, I overlooked that TermIterator creates temporary string (if I\r
+understand you correctly).\r
+\r
+> \r
+>      string s = *i;\r
+>\r
+> in function scope, and replacing (*i) with s in the if block. This might\r
+> also be more obvious than the presented patch, but I think the patch is\r
+> fine too.\r
+\r
+I would prefer my change as it avoids creating another std::string. At\r
+least I think.\r
+\r
+Thank you\r
+-- \r
+       Vlad\r