> On May 1, 2020 at 7:39 AM Jonathan Wakely wrote: > > On Thu, 30 Apr 2020 at 23:58, Tom N wrote:>> > On April 30, 2020 at 5:57 PM Jonathan Wakely wrote:The man page says:"Unlike other similar options, -fsanitize=float-divide-by-zero is not enabled by -fsanitize=undefined" and "Unlike other similar options,-fsanitize=float-cast-overflow is not enabled by -fsanitize=undefined"So it seems reasonable to assume that all the other suboptions are enabled by -fsanitize=undefined, and if you want *all* of them then use -fsanitize=undefined -fsanitize=float-divide-by-zero-fsanitize=float-cast-overflow> Thanks for the tip. Any reason the description of -fsanitize=undefined doesn't include something like, "If the -fsanitize=undefined option is enabled all sub-options will be enabled unless otherwise specified." so it's clear?Probably because nobody has suggested doing that yet. Would you liketo propose a patch for the docs? > The relevant place is here:https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/doc/invoke.texi;h=527d362533ab503cee9568b27808177977a52ac8;hb=HEAD#l13541 I'd be happy to but unfortunately I'm not familiar with git. (I know...). But here's an old-style patch off 8.4 if it helps (attached too): ----- --- gcc-8.4.0/gcc/doc/invoke.texi 2020-03-04 03:30:00.000000000 -0500 +++ gcc-8.4.0_new/gcc/doc/invoke.texi 2020-05-01 13:10:36.517390533 -0400 @@ -11404,7 +11404,8 @@ @opindex fsanitize=undefined Enable UndefinedBehaviorSanitizer, a fast undefined behavior detector. Various computations are instrumented to detect undefined behavior -at runtime. Current suboptions are: +at runtime. If this option is enabled all sub-options listed below will be +enabled unless otherwise specified. Current suboptions are: @table @gcctabopt -----