managed_scip: fix storage of power exponent

- don't use separate EXPR_CONST - this would lead to memory leak - see discussion at scipopt/CSIP#28
scipopt · Feb 22, 2019 · f17720e · f17720e
1 parent eda856e
commit f17720e
Show file tree

Hide file tree

Showing 2 changed files with 5 additions and 6 deletions.
diff --git a/src/managed_scip.jl b/src/managed_scip.jl
@@ -286,8 +286,7 @@ function add_nonlinear_constraint(mscip::ManagedSCIP, operators::Vector{SCIP_Exp
         elseif op == SCIP_EXPR_REALPOWER
             nchildren == 2 || error("Need two children for op. $(op)!")
             base = exprs[children[offsets[i]]]
-            exponent_expr = children[offsets[i] + 1] # is SCIP_EXPR_CONST,
-            exponent = values[children[offsets[exponent_expr]]] # directly get value
+            exponent = values[children[offsets[i] + 1]]
             @SC SCIPexprCreate(SCIPblkmem(mscip), expr__, op, base, exponent)
         elseif op == SCIP_EXPR_DIV
             nchildren == 2 || error("Need two children for op. $(op)!")

diff --git a/test/managed_scip.jl b/test/managed_scip.jl
@@ -33,10 +33,10 @@ end
         # abspower:  y == sign(x) * |x|^2 ( == x * |x| )
         a = SCIP.add_abspower_constraint(mscip, x, 0.0, 2.0, y, -1.0, 0.0, 0.0)
         # nonlinear: x^0.2 == 1
-        _operators = [SCIP.SCIP_EXPR_VARIDX, SCIP.SCIP_EXPR_CONST, SCIP.SCIP_EXPR_REALPOWER]
-        _offsets   = [1,     2,   3,    5]
-        _children  = [x.val, 1,   1, 2] # extract integer from VarRef!
-        _values    = [       0.2]
+        _operators = [SCIP.SCIP_EXPR_VARIDX, SCIP.SCIP_EXPR_REALPOWER]
+        _offsets   = [1, 2, 4]
+        _children  = [x.val, 1, 1] # extract integer from VarRef!
+        _values    = [0.2]
         n = SCIP.add_nonlinear_constraint(mscip, _operators, _offsets,
                                           _children, _values, 1.0, 1.0)