Only build the x86 arches we actually need.

build/nacl_core_sdk.gyp

Index: build/nacl_core_sdk.gyp
diff --git a/build/nacl_core_sdk.gyp b/build/nacl_core_sdk.gyp
index 83dddad494b44f3dff080d4f990a50e9151c7a60..888f6c59d9d9960e53aab43d26f59a3e508ebdf3 100644
--- a/build/nacl_core_sdk.gyp
+++ b/build/nacl_core_sdk.gyp
@@ -38,6 +38,8 @@
             '../src/untrusted/valgrind/valgrind.gyp:dynamic_annotations_lib',
             '../src/untrusted/valgrind/valgrind.gyp:valgrind_lib',
           ],
+        }],
+        ['target_arch=="ia32"', {
           'copies': [
             {
               'destination': '<(SHARED_INTERMEDIATE_DIR)/sdk/<(OS)_x86/nacl_x86_newlib/x86_64-nacl/lib32',
@@ -52,6 +54,19 @@
               ],
             },
             {
+              'destination': '<(SHARED_INTERMEDIATE_DIR)/sdk/<(OS)_x86/nacl_x86_glibc/x86_64-nacl/lib32',
+              'files': [
+                '<(SHARED_INTERMEDIATE_DIR)/tc_glibc/lib32/libnacl_dyncode.a',
+                '<(SHARED_INTERMEDIATE_DIR)/tc_glibc/lib32/libnacl_list_mappings.a',
+                '<(SHARED_INTERMEDIATE_DIR)/tc_glibc/lib32/libvalgrind.a',
+                '<(SHARED_INTERMEDIATE_DIR)/tc_glibc/lib32/libdynamic_annotations.a',
+              ],
+            },
+          ],
+        }],
+        ['target_arch=="x64" or (target_arch=="ia32" and OS=="win")', {
+          'copies': [
+            {
               'destination': '<(SHARED_INTERMEDIATE_DIR)/sdk/<(OS)_x86/nacl_x86_newlib/x86_64-nacl/lib',
               'files': [
                 '<(SHARED_INTERMEDIATE_DIR)/tc_newlib/lib64/crti.o',
@@ -64,15 +79,6 @@
               ],
             },
             {
-              'destination': '<(SHARED_INTERMEDIATE_DIR)/sdk/<(OS)_x86/nacl_x86_glibc/x86_64-nacl/lib32',
-              'files': [
-                '<(SHARED_INTERMEDIATE_DIR)/tc_glibc/lib32/libnacl_dyncode.a',
-                '<(SHARED_INTERMEDIATE_DIR)/tc_glibc/lib32/libnacl_list_mappings.a',
-                '<(SHARED_INTERMEDIATE_DIR)/tc_glibc/lib32/libvalgrind.a',
-                '<(SHARED_INTERMEDIATE_DIR)/tc_glibc/lib32/libdynamic_annotations.a',
-              ],
-            },
-            {
               'destination': '<(SHARED_INTERMEDIATE_DIR)/sdk/<(OS)_x86/nacl_x86_glibc/x86_64-nacl/lib',
               'files': [
                 '<(SHARED_INTERMEDIATE_DIR)/tc_glibc/lib64/libnacl_dyncode.a',