Index: tree-sra.c =================================================================== --- tree-sra.c (revision 120483) +++ tree-sra.c (working copy) @@ -670,8 +670,8 @@ struct sra_walk_fns void (*init) (struct sra_elt *elt, tree value, block_stmt_iterator *bsi); /* Invoked when we have a copy between one scalarizable reference ELT - and one non-scalarizable reference OTHER. IS_OUTPUT is true if ELT - is on the left-hand side. */ + and one non-scalarizable reference OTHER without side-effects. + IS_OUTPUT is true if ELT is on the left-hand side. */ void (*ldst) (struct sra_elt *elt, tree other, block_stmt_iterator *bsi, bool is_output); @@ -887,7 +887,7 @@ sra_walk_gimple_modify_stmt (tree expr, /* If the RHS is scalarizable, handle it. There are only two cases. */ if (rhs_elt) { - if (!rhs_elt->is_scalar) + if (!rhs_elt->is_scalar && !TREE_SIDE_EFFECTS (lhs)) fns->ldst (rhs_elt, lhs, bsi, false); else fns->use (rhs_elt, &GIMPLE_STMT_OPERAND (expr, 1), bsi, false, false); @@ -930,7 +930,8 @@ sra_walk_gimple_modify_stmt (tree expr, The lvalue requirement prevents us from trying to directly scalarize the result of a function call. Which would result in trying to call the function multiple times, and other evil things. */ - else if (!lhs_elt->is_scalar && is_gimple_addressable (rhs)) + else if (!lhs_elt->is_scalar + && !TREE_SIDE_EFFECTS (rhs) && is_gimple_addressable (rhs)) fns->ldst (lhs_elt, rhs, bsi, true); /* Otherwise we're being used in some context that requires the