On Sat, 23 Jan 2016 22:05:39 GMT, Alv wrote:

Hello,

My D program was progressing nicely, until I �tested� it with release mode and got a linker error.

Severity Code Description Project File Line Suppression State
Error Error 42: Symbol Undefined D4vibe4core3log162T8logTraceVAyaa63433a5c445c646d64325c77696e646f77735c62696e5c2e2e5c2e2e5c74E19315AD33F01AC918E4DA11CD373D4 C:\Data\Dev\program\

This function is:
void logTrace(string file = FILE, int line = LINE, S, T...)(S fmt, lazy T args) nothrow { log!(LogLevel.trace)(fmt, args); }

When I include the log module in my own project AND remove the body of the function:
void logTrace(string file = FILE, int line = LINE, S, T...)(S fmt, lazy T args) nothrow { }

it links fine.

My config:
Win7/64bit, Visual Studio / Visual D 0.3
DMD v2.069.2
vibe-d-0.7.26

Any solution or suggestions what to investigate next?

This must be a DMD bug. If you can provide a test case, you should ideally file a bug report on http://issues.dlang.org.

One thing to try to work around this is to use the --combined switch when running DUB. Another is to enable the --allinst switch of DMD, using a build type customization of the "release" configuration.