The api.value.automove directive doesn't honor an explicit false setting.
-------------------------------------------// test_automove.y%skeleton 
"lalr1.cc"%require "3.8"%language "c++"%define api.value.automove false
%token <int> VAL%nterm <int> x%%x: 
VAL-------------------------------------------
bison -o test_automove.cpp test_automove.y
grep -B2 "yylhs.value.int" test_automove.bison.cpp
  case 2: // x: VAL#line 11 "test_automove.bison.y"   { (yylhs.value.int) = 
YY_MOVE ((yystack_[0].value.int)); }
bison --versionbison (GNU Bison) 3.8.2
-------------------------------------------
The problem is in skeletons/lalr1.cc where b4_percent_define_ifdef applies 
YY_MOVE as long as api.value.automove is defined without considering its value
The default value of api.value.automove is false - omitting the directive does 
prevent YY_MOVE from being applied
m4_define([b4_rhs_value],[b4_percent_define_ifdef([api.value.automove],         
                [YY_MOVE (_b4_rhs_value($@))],                         
[_b4_rhs_value($@)])])
-------------------------------------------
b4_percent_define_ifdef is defined in skeletons/bison.m4
# _b4_percent_define_ifdef(VARIABLE, IF-TRUE, [IF-FALSE])# 
------------------------------------------------------# If the %define variable 
VARIABLE is defined, expand IF-TRUE, else expand# IF-FALSE.  Don't record usage 
of VARIABLE.
-------------------------------------------
I'll send a fix for lalr1.cc shortly to bison-patches that looks like this
111a112,114> # api.value.automove boolean default value false> 
b4_percent_define_default([[api.value.automove]], [[false]])>113,115c116,118< 
[b4_percent_define_ifdef([api.value.automove],<                          
[YY_MOVE (_b4_rhs_value($@))],<                          
[_b4_rhs_value($@)])])---> [b4_percent_define_flag_if([api.value.automove],>    
                      [YY_MOVE /* ztm true */ (_b4_rhs_value($@))],>            
              [/* ztm false */_b4_rhs_value($@)])])

Zartaj

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