Fix expansion of several macros per line

src/include/build.sh

     local line=$1   # line to process
     local mname     # macro name
     local mvline    # line of macro value
+    local xline     # expanded line
+    xline=$line
     for mname in "${!MacroMap[@]}"; do
         if ! test "${line//$mname}" == "$line"; then
-            while IFS= read -r mvline; do
-                echo "${line//$mname/$mvline}"
-            done <<<"${MacroMap[$mname]}"
-            return 0
+            xline=$(
+                while IFS= read -r mvline; do
+                    echo "${line//$mname/$mvline}"
+                done <<<"${MacroMap[$mname]}"
+            )
         fi
+        line=$xline
     done
-    echo "$line"
+    echo "$xline"
     return 1
 }