More updates to build optimization settings.

build/SConscript.main

Index: build/SConscript.main
diff --git a/build/SConscript.main b/build/SConscript.main
index 15865ce97d4e51be17eb32ea5596095a8fb712d5..6d5970e859c7f0b8641661c7956a26415a9d8402 100644
--- a/build/SConscript.main
+++ b/build/SConscript.main
@@ -511,6 +511,11 @@ linux_env.Append(
 # Build an "official" build (DCHECKs completely compiled out, etc).
 if ARGUMENTS.get('OFFICIAL') == '1':
   linux_env.Append(CPPDEFINES=['OFFICIAL_BUILD'])
+  # Make sure units of code and data go in their own section, and then GC them
+  # in the linker to remove unreferenced data and code.  Currently gold doesn't
+  # support --gc-sections, so you'll have to build with the original GNU ld.
+  linux_env.Append(CCFLAGS_OPTIMIZED=['-ffunction-sections', '-fdata-sections'])
+  linux_env.Append(LINKFLAGS_OPTIMIZED=['-Wl,--gc-sections'])
 
 # Build with support for gcov when COVERAGE=1.
 if ARGUMENTS.get('COVERAGE') == '1':
@@ -523,12 +528,8 @@ if ARGUMENTS.get('PROFILE') == '1':
   linux_env.Append(LINKFLAGS=['-pg'])
 
 # Build with symbols (useful for opt builds, for example) when SYMBOLS=1.
-# Otherwise if we're building release, strip all symbols from our output.
 if ARGUMENTS.get('SYMBOLS') == '1':
   linux_env.Append(CCFLAGS=['-g'])
-else:
-  linux_env.Append(CCFLAGS_OPTIMIZED=['-ffunction-sections', '-fdata-sections'])
-  linux_env.Append(LINKFLAGS_OPTIMIZED=['-Wl,--gc-sections', '-s'])
 
 # Build shared libraries (useful for fast links) when SHARED=1.
 if ARGUMENTS.get('SHARED') == '1':