From 0c62356cc8777961221a643fa77f62e1c7361085 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Wed, 14 Feb 2018 15:06:01 -0500 Subject: [PATCH] Add an assertion that we don't pass NULL to snprintf("%s"). Per commit e748e902d, we appear to have little or no coverage in the buildfarm of machines that will dump core when asked to printf a null string pointer. Let's try to improve that situation by adding an assertion that will make src/port/snprintf.c behave that way. Since it's just an assertion, it won't break anything in production builds, but it will help developers find this type of oversight. Note that while our buildfarm coverage of machines that use that snprintf implementation is pretty thin on the Unix side (apparently amounting only to gaur/pademelon), all of the MSVC critters use it. Discussion: https://postgr.es/m/156b989dbc6fe7c4d3223cf51da61195@postgrespro.ru --- src/port/snprintf.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/port/snprintf.c b/src/port/snprintf.c index 43c17e702e..8358425980 100644 --- a/src/port/snprintf.c +++ b/src/port/snprintf.c @@ -745,6 +745,8 @@ nextch2: strvalue = argvalues[fmtpos].cptr; else strvalue = va_arg(args, char *); + /* Whine if someone tries to print a NULL string */ + Assert(strvalue != NULL); fmtstr(strvalue, leftjust, fieldwidth, precision, pointflag, target); break; -- 2.40.0