Apple M1: More robust build for universal binaries

- Fixed a typo in the Readme.md
- Made the recursiveMergeBinaries function handle divergent binary file trees
  better.

BuildMacOSUniversalBinary.py

@@ -175,11 +175,14 @@ def recursiveMergeBinaries(src0, src1, dst):
 
     # Loop over files in src1 and copy missing things over to dst
     for newpath1 in glob.glob(src1+"/*"):
-        filename = os.path.basename(newpath0)
+        filename = os.path.basename(newpath1)
         newpath0 = os.path.join(src0, filename)
         new_dst_path = os.path.join(dst, filename)
-        if not os.path.exists(newpath0) and not os.path.islink(newpath1):
-            shutil.copytree(newpath1, new_dst_path)
+        if (not os.path.exists(newpath0)) and (not os.path.islink(newpath1)):
+            if os.path.isdir(newpath1):
+                shutil.copytree(newpath1, new_dst_path)
+            else:
+                shutil.copy(newpath1, new_dst_path)
 
     # Fix up symlinks for path0
     for newpath0 in glob.glob(src0+"/*"):

Readme.md

@@ -69,7 +69,7 @@ application bundle using the following steps:
 
 1. `mkdir build`
 2. `cd build`
-3. `python ../BuildMacOSUniveralBinary.py`
+3. `python ../BuildMacOSUniversalBinary.py`
 4. Universal binaries will be available in the `universal` folder
 
 Doing this requires installation of library dependencies for both x64 and ARM (or universal library