start with wc

build.sh

@@ -1,3 +1,11 @@
+assemble () {
+  FILE="$1"
+  PROGRAM_NAME="$2"
+
+  echo "Assembling $PROGRAM_NAME"
+  nasm -g -F dwarf -f elf64 "$FILE" -o "./target/$PROGRAM_NAME.o" || return
+}
+
 build () {
     FILE="$1"
     PROGRAM_NAME=$(basename "$FILE" ".asm")
@@ -7,8 +15,16 @@ build () {
         return
     fi
 
-    echo "Building $PROGRAM_NAME"
-    nasm -g -F dwarf -f elf64 "$FILE" -o "./target/$PROGRAM_NAME.o" && ld.lld "./target/$PROGRAM_NAME.o" -o "./target/$PROGRAM_NAME"
+
+    if [ "$PROGRAM_NAME" = "common" ]; then
+      # common does not need to be linked into an executable
+      return
+    fi
+
+    assemble "$FILE" "$PROGRAM_NAME"
+
+    echo "Linking $PROGRAM_NAME"
+    ld.lld "./target/$PROGRAM_NAME.o" "./target/common.o" -o "./target/$PROGRAM_NAME"
 }
 
 
@@ -21,6 +37,9 @@ if [ ! -d ./target ]; then
   mkdir ./target
 fi
 
+
+assemble "src/common.asm" "common"
+
 if [ "$#" -eq 0 ]; then
   for FILE in ./src/*.asm ; do
     build "$FILE"