自从将
Xcode更新到6.3版以来,我在编译C代码时收到了以下警告：
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/module.map:1:25: warning: unknown attribute 'extern_c' [-Wignored-attributes]
module Darwin [system] [extern_c] {
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/module.map:1561:21: warning: unknown attribute 'extern_c' [-Wignored-attributes]
module os [system] [extern_c] {
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/module.map:1577:26: warning: unknown attribute 'extern_c' [-Wignored-attributes]
module libkern [system] [extern_c] {
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/module.map:1602:23: warning: unknown attribute 'extern_c' [-Wignored-attributes]
module ldap [system] [extern_c] {
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/module.map:1635:23: warning: unknown attribute 'extern_c' [-Wignored-attributes]
module krb5 [system] [extern_c] {
^
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/module.map:1662:22: warning: unknown attribute 'extern_c' [-Wignored-attributes]
module XPC [system] [extern_c] {
^
解决方法
事实证明我使用旧版本的clang和Xcode的SDK.使用默认的clang删除警告.