Export memory only when EXPORT_ALL is defined

Author: llucinat

README.markdown

@@ -37,7 +37,7 @@ The script also produces an optimized module using `wasm-opt -O3` from the *bina
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-- `EXPORT_ALL` exports functions other than `cmem_init` and `cmem_end`, including memory and list management functions.
+- `EXPORT_ALL` exports the memory and functions other than `cmem_init` and `cmem_end`, including memory and list management functions.
 - `PREFIX_LIBC` prepends `cmem_` to libc function names.
 - `FIRST_FIT` employs a first-fit instead of a best-fit strategy for allocation.
 - `BULK_MEMORY` enables use of bulk memory instructions, decreasing embedder compatibility.

cmem.wat

@@ -46,7 +46,12 @@
 
 (module
 
-	(memory (export "memory") 1)
+	(memory
+#ifdef EXPORT_ALL
+		(export "memory")
+#endif
+	1)
+
 	(global $cmem_begin (mut i32) (i32.const 0))
 	(global $cmem_last (mut i32) (i32.const 0))