Fix a bug where precompiled list of SDKs would not attempted to be downloaded if git was not present on the system. Fixes https://github.com/kripken/emscripten/issues/6165.

emsdk

@@ -1508,21 +1508,10 @@ def python_2_3_sorted(arr, cmp):
 
 def fetch_emscripten_tags():
   git = GIT(must_succeed=False)
-  if not git:
-    print('Update complete, however skipped fetching the Emscripten tags, since git was not found.')
-    if WINDOWS:
-      print("If you want to compile one of the tagged releases from source, please install git by typing 'emsdk install git-1.9.4', or alternatively by installing it manually from http://git-scm.com/downloads . If you install git manually, remember to add it to PATH.")
-    elif OSX:
-      print("If you want to compile one of the tagged releases from source, please install git from http://git-scm.com/ , or by installing XCode and then the XCode Command Line Tools (see http://stackoverflow.com/questions/9329243/xcode-4-4-command-line-tools ).")
-    elif LINUX:
-      print("If you want to compile one of the tagged releases from source, please install git using your package manager, see http://git-scm.com/book/en/Getting-Started-Installing-Git .")
-    else:
-      print("If you want to compile one of the tagged releases from source, please install git.")
-    print("If you are not looking to build Emscripten from source, you can safely ignore this message.")
-    return
 
+  if git:
     print('Fetching all tags from Emscripten Github repository...')
-  tags = run_get_output([GIT(), 'ls-remote', '--tags', emscripten_git_repo])
+    tags = run_get_output([git, 'ls-remote', '--tags', emscripten_git_repo])
     if tags[0] != 0: return False # failed to get tags?
     tags = tags[1]
     all_tags = []
@@ -1541,7 +1530,7 @@ def fetch_emscripten_tags():
       print('Done. No tagged releases available.')
 
     print('Fetching all tags from Binaryen Github repository...')
-  tags = run_get_output([GIT(), 'ls-remote', '--tags', binaryen_git_repo])
+    tags = run_get_output([git, 'ls-remote', '--tags', binaryen_git_repo])
     if tags[0] != 0: return False # failed to get tags?
     tags = tags[1]
     binaryen_tags = []
@@ -1576,6 +1565,19 @@ def fetch_emscripten_tags():
   download_file('https://s3.amazonaws.com/mozilla-games/emscripten/packages/llvm/tag/' + os_name_for_llvm_location() + '_32bit/index.txt', 'llvm-tags-32bit.txt', download_even_if_exists=True)
   download_file('https://s3.amazonaws.com/mozilla-games/emscripten/packages/llvm/tag/' + os_name_for_llvm_location() + '_64bit/index.txt', 'llvm-tags-64bit.txt', download_even_if_exists=True)
 
+  if not git:
+    print('Update complete, however skipped fetching the Emscripten tags, since git was not found.')
+    if WINDOWS:
+      print("If you want to compile one of the tagged releases from source, please install git by typing 'emsdk install git-1.9.4', or alternatively by installing it manually from http://git-scm.com/downloads . If you install git manually, remember to add it to PATH.")
+    elif OSX:
+      print("If you want to compile one of the tagged releases from source, please install git from http://git-scm.com/ , or by installing XCode and then the XCode Command Line Tools (see http://stackoverflow.com/questions/9329243/xcode-4-4-command-line-tools ).")
+    elif LINUX:
+      print("If you want to compile one of the tagged releases from source, please install git using your package manager, see http://git-scm.com/book/en/Getting-Started-Installing-Git .")
+    else:
+      print("If you want to compile one of the tagged releases from source, please install git.")
+    print("If you are not looking to build Emscripten from source, you can safely ignore this message.")
+    return
+
 def is_emsdk_sourced_from_github():
   return os.path.exists(os.path.join(emsdk_path(), '.git'))