warn about ASM_JS

2 files changed, 4 insertions, 1 deletions

diff --git a/emcc b/emcc
index c2b10862..8aae6be1 100755
--- a/emcc
+++ b/emcc
@@ -1144,6 +1144,7 @@ try:
     if DEBUG: save_intermediate('transformed')
 
   if shared.Settings.ASM_JS: # XXX temporary wrapping for testing purposes
+    print >> sys.stderr, 'emcc: ASM_JS mode is highly experimental, and will not work on most codebases yet. It is NOT recommended that you try this yet.'
     unwrapped = open(final).read()
     final += '.asmwrap.js'
     open(final, 'w').write('''
diff --git a/src/settings.js b/src/settings.js
index 3d32db9e..c530b083 100644
--- a/src/settings.js
+++ b/src/settings.js
@@ -301,7 +301,9 @@ var HEADLESS = 0; // If 1, will include shim code that tries to 'fake' a browser
                   // very partial - it is hard to fake a whole browser! - so
                   // keep your expectations low for this to work.
 
-var ASM_JS = 0; // If 1, generate code in asm.js format
+var ASM_JS = 0; // If 1, generate code in asm.js format. XXX This is highly experimental,
+                // and will not work on most codebases yet. It is NOT recommended that you
+                // try this yet.
 var USE_MATH_IMUL = 0; // If 1, use Math.imul when useful
 
 var NECESSARY_BLOCKADDRS = []; // List of (function, block) for all block addresses that are taken.