For GCC versions before 4.3 we still use the "-Wconversion" flag so if we build with such a GCC the code introduced by "8048150: Allow easy configurations for large CDS archives" will trigger the following warnings which are treated as errors:

/src/hotspot-rt/src/share/vm/memory/metaspaceShared.cpp: In static member function 'static void MetaspaceShared::estimate_regions_size()':
/src/hotspot-rt/src/share/vm/memory/metaspaceShared.cpp:1124: warning: converting to 'uintx' from 'double'
/src/hotspot-rt/src/share/vm/memory/metaspaceShared.cpp:1125: warning: converting to 'uintx' from 'double'
/src/hotspot-rt/src/share/vm/memory/metaspaceShared.cpp:1126: warning: converting to 'uintx' from 'double'
/src/hotspot-rt/src/share/vm/memory/metaspaceShared.cpp:1127: warning: converting to 'uintx' from 'double'
/src/hotspot-rt/src/share/vm/memory/metaspaceShared.cpp:1129: warning: converting to 'uintx' from 'double'
/src/hotspot-rt/src/share/vm/memory/metaspaceShared.cpp:1130: warning: converting to 'uintx' from 'double'
/src/hotspot-rt/src/share/vm/memory/metaspaceShared.cpp:1131: warning: converting to 'uintx' from 'double'
/src/hotspot-rt/src/share/vm/memory/metaspaceShared.cpp:1132: warning: converting to 'uintx' from 'double'

The fix is trivial - just implicitly cast the result of the conversion to uintx:

diff -r 8ae56f4f758f src/share/vm/memory/metaspaceShared.hpp
--- a/src/share/vm/memory/metaspaceShared.hpp Tue Aug 26 13:07:57 2014 -0700
+++ b/src/share/vm/memory/metaspaceShared.hpp Wed Aug 27 16:43:39 2014 +0200
@@ -41,7 +41,7 @@
 
 #define SET_ESTIMATED_SIZE(type, region) \
   Shared ##region## Size = FLAG_IS_DEFAULT(Shared ##region## Size) ? \
- (type ## SharedArchiveSize * region ## RegionPercentage) : Shared ## region ## Size
+ (uintx)(type ## SharedArchiveSize * region ## RegionPercentage) : Shared ## region ## Size
 
 class FileMapInfo;