allow -O3 in compilation units

diff --git a/qcsrc/tools/compilationunits.sh b/qcsrc/tools/compilationunits.sh
index e3d1eb01368df1c714c55d7264eda99e89ff8bbd..68f2eb9d5628ae7df244e70e2ef158be1d69124b 100755 (executable)
--- a/qcsrc/tools/compilationunits.sh
+++ b/qcsrc/tools/compilationunits.sh
@@ -38,6 +38,7 @@ QCCDEFS="${QCCDEFS[@]}"
 
 declare -a QCCFLAGS=(
     -std=gmqcc
+    -O3 # optimization to accept variable initialization inside `if (1)` blocks and avoid warnings
     -Wall -Werror
     -futf8
     -freturn-assignments