diff --git a/demos/asm/header.h b/demos/asm/header.h
new file mode 100644
index 00000000..fc9ed4f3
--- /dev/null
+++ b/demos/asm/header.h
@@ -0,0 +1 @@
+#define SOME_VALUE 0x1111
diff --git a/demos/asm/test.S b/demos/asm/test.S
index cbbd1659..32217583 100644
--- a/demos/asm/test.S
+++ b/demos/asm/test.S
@@ -1,3 +1,4 @@
+#include "header.h"
 
 .text
 .align 2
diff --git a/waflib/Tools/gas.py b/waflib/Tools/gas.py
index 81e4dce8..9c3dfb59 100644
--- a/waflib/Tools/gas.py
+++ b/waflib/Tools/gas.py
@@ -11,7 +11,7 @@ def configure(conf):
 	"""
 	Find the programs gas/as/gcc and set the variable *AS*
 	"""
-	conf.find_program(['gas', 'as', 'gcc'], var='AS')
-	conf.env.AS_TGT_F = ['-o']
+	conf.find_program(['gas', 'gcc'], var='AS')
+	conf.env.AS_TGT_F = ['-c', '-o']
 	conf.env.ASLNK_TGT_F = ['-o']
 	conf.find_ar()