The program can't start because cygwin1.dll is missing... in Eclipse CDT

Question

I've had Eclipse for Java on my computer for a few years, and decided to install the CDT and learn C. I installed both MinGW and Cygwin and the CDT detects and tries to use them when I make a new project.

I choose File > New C++ Project and choose Hello World C++ Project and the CygwinGCC toolchain. I name the project "asdf" and hit "Build Debug" in the toolbar. The compiler completes without error. I hit Run and nothing happens.

Browsing to the project directory manually and running asdf.exe gives me an error saying:
"The program can't start because cygwin1.dll is missing from your computer. Try reinstalling the program to fix this problem."

The same thing happens using MinGW, only a different dll is missing.
What do I need to do to have a usable .exe?
(I'm running Windows 7 x64 and the newest version of Eclipse and the CDT.)

EDIT: The compiler output is as follows:

**** Build of configuration Debug for project asdf ****

make all 
Building file: ../src/asdf.cpp
Invoking: Cygwin C++ Compiler
g++ -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"src/asdf.d" -MT"src/asdf.d" -o"src/asdf.o" "../src/asdf.cpp"
cygwin warning:
  MS-DOS style path detected: C:\Users\Shawn\Dropbox\eclipse\asdf\Debug
  Preferred POSIX equivalent is: /cygdrive/c/Users/Shawn/Dropbox/eclipse/asdf/Debug
  CYGWIN environment variable option "nodosfilewarning" turns off this warning.
  Consult the user's guide for more details about POSIX paths:
    http://cygwin.com/cygwin-ug-net/using.html#using-pathnames
Finished building: ../src/asdf.cpp

Building target: asdf.exe
Invoking: Cygwin C++ Linker
g++  -o"asdf.exe"  ./src/asdf.o   
Finished building target: asdf.exe

Answer 1

This error message means that Windows isn't able to find "cygwin1.dll". The Programs that the Cygwin gcc create depend on this DLL. The file is part of cygwin , so most likely it's located in C:\cygwin\bin. To fix the problem all you have to do is add C:\cygwin\bin (or the location where cygwin1.dll can be found) to your system path. Alternatively you can copy cygwin1.dll into your Windows directory.

There is a nice tool called DependencyWalker that you can download from http://www.dependencywalker.com . You can use it to check dependencies of executables, so if you inspect your generated program it tells you which dependencies are missing and which are resolved.