Document -fallocation-dce.

2019-11-14  Martin Liska  <mliska@suse.cz>

	PR other/92329
	* doc/invoke.texi: Document -fallocation-dce.

From-SVN: r278211

gcc/ChangeLog

 2019-11-14  Martin Liska  <mliska@suse.cz>
 
+	PR other/92329
+	* doc/invoke.texi: Document -fallocation-dce.
+
+2019-11-14  Martin Liska  <mliska@suse.cz>
+
 	PR target/92389
 	* config/i386/i386.h: Add PTA_AVX512VPOPCNTDQ to
 	PTA_ICELAKE_CLIENT which is later interited by

gcc/doc/invoke.texi

@@ -407,7 +407,7 @@ Objective-C and Objective-C++ Dialects}.
 -falign-jumps[=@var{n}[:@var{m}:[@var{n2}[:@var{m2}]]]] @gol
 -falign-labels[=@var{n}[:@var{m}:[@var{n2}[:@var{m2}]]]] @gol
 -falign-loops[=@var{n}[:@var{m}:[@var{n2}[:@var{m2}]]]] @gol
--fallow-store-data-races @gol
+-fno-allocation-dce -fallow-store-data-races @gol
 -fassociative-math  -fauto-profile  -fauto-profile[=@var{path}] @gol
 -fauto-inc-dec  -fbranch-probabilities @gol
 -fcaller-saves @gol
@@ -10267,6 +10267,10 @@ The maximum allowed @var{n} option value is 65536.
 
 Enabled at levels @option{-O2}, @option{-O3}.
 
+@item -fno-allocation-dce
+@opindex fno-allocation-dce
+Do not remove unused C++ allocations in dead code elimination.
+
 @item -fallow-store-data-races
 @opindex fallow-store-data-races
 Allow the compiler to introduce new data races on stores.