https://issues.dlang.org/show_bug.cgi?id=19051
Issue ID: 19051 Summary: Undefined functions Set/GetWindowLongPtr in mingw libs Product: D Version: D2 Hardware: x86_64 OS: Windows Status: NEW Severity: normal Priority: P1 Component: dmd Assignee: nob...@puremagic.com Reporter: chrismohrf...@comcast.net Linking fails when using SetWindowLongPtr and GetWindowLongPtr from core.sys.windows.winuser and compiling to 64-bit. void main() { import std.stdio; import core.sys.windows.winuser; writeln("SetWindowLongPtr = ", SetWindowLongPtr(null, 0, 0)); writeln("GetWindowLongPtr = ", GetWindowLongPtr(null, 0)); } dmd test.d -m64 C:\dmd2\windows\bin\lld-link.exe: warning: test.obj: undefined symbol: SetWindowLongPtrW C:\dmd2\windows\bin\lld-link.exe: warning: test.obj: undefined symbol: GetWindowLongPtrW error: link failed Error: linker exited with status 1 Issue appears to be that these functions are not defined in the mingw 64-bit user32.lib --