4 files changed, 16 insertions, 7 deletions
diff --git a/acprep b/acprep
index 1fac5d35..81a4a853 100755
--- a/acprep
+++ b/acprep
@@ -26,6 +26,10 @@ elif [ "$1" = "--opt" ]; then
 elif [ "$1" = "--flat-opt" ]; then
     ./configure CPPFLAGS="$INCDIRS" LDFLAGS="$LIBDIRS" \
 	CXXFLAGS="-fomit-frame-pointer -fastf -mcpu=7450" --disable-shared
+elif [ "$1" = "--safe-opt" ]; then
+    ./configure CPPFLAGS="$INCDIRS" LDFLAGS="$LIBDIRS" \
+	CXXFLAGS="-fomit-frame-pointer -fastf -mcpu=7450 -DDEBUG_LEVEL=1" \
+	--disable-shared
 elif [ "$1" = "--perf" ]; then
     ./configure CPPFLAGS="$INCDIRS" LDFLAGS="$LIBDIRS" CXXFLAGS="-g -pg"
 fi
diff --git a/amount.cc b/amount.cc
index 1a538f40..69ac1738 100644
--- a/amount.cc
+++ b/amount.cc
@@ -489,9 +489,11 @@ amount_t::operator bool() const
   if (quantity->prec <= commodity().precision) {
     return mpz_sgn(MPZ(quantity)) != 0;
   } else {
-    assert(commodity_);
     mpz_set(temp, MPZ(quantity));
-    mpz_ui_pow_ui(divisor, 10, quantity->prec - commodity().precision);
+    if (commodity_)
+      mpz_ui_pow_ui(divisor, 10, quantity->prec - commodity_->precision);
+    else
+      mpz_ui_pow_ui(divisor, 10, quantity->prec);
     mpz_tdiv_q(temp, temp, divisor);
     bool zero = mpz_sgn(temp) == 0;
     return ! zero;
diff --git a/format.h b/format.h
index f3bf671c..5f6518fd 100644
--- a/format.h
+++ b/format.h
@@ -115,9 +115,10 @@ class format_entries : public format_transactions
   void format_last_entry();
 
   virtual void flush() {
-    format_last_entry();
-    last_entry = NULL;
-
+    if (last_entry) {
+      format_last_entry();
+      last_entry = NULL;
+    }
     format_transactions::flush();
   }
   virtual void operator()(transaction_t& xact);
diff --git a/walk.h b/walk.h
index 39a220be..0ac9e133 100644
--- a/walk.h
+++ b/walk.h
@@ -306,8 +306,10 @@ class changed_value_transactions : public item_handler<transaction_t>
       changed_values_only(_changed_values_only), last_xact(NULL) {}
 
   virtual void flush() {
-    output_diff(std::time(NULL));
-    last_xact = NULL;
+    if (last_xact) {
+      output_diff(std::time(NULL));
+      last_xact = NULL;
+    }
     item_handler<transaction_t>::flush();
   }