Recent GCC versions need more memory.

src/ljamalg.c

@@ -6,7 +6,7 @@
 /*
 +--------------------------------------------------------------------------+
 | WARNING: Compiling the amalgamation needs a lot of virtual memory        |
-| (around 200 MB with GCC 4.x)! If you don't have enough physical memory   |
+| (around 300 MB with GCC 4.x)! If you don't have enough physical memory   |
 | your machine will start swapping to disk and the compile will not finish |
 | within a reasonable amount of time.                                      |
 | So either compile on a bigger machine or use the non-amalgamated build.  |