LibRaw 0.5.5 and 0.6.0-Beta2 have minor issues fixed:

• Enum definitions changed to make gcc -pedantic happy
• Compiler/preprocessor flags does not affects LibRaw class field set (i.e. structure for thread local storage is always allocated)
• Default library compilation mode (i.e. sources imported in another project) is thread-safe

Your can always download latest LibRaw version from this site's download page.