I've done fresh install of cygwin with setup-x86.exe @ Win10 LTSB 2015 x64.

I've installed gcc-core and w32api-runtime packages.

opengl32.dll in System32 folder is 32-bit dll

With x86_64 install of cygwin ld able to find reference to wglCreateContext, with x86 - not.

$ gcc -o /tmp/conftest.exe /tmp/conftest.c -lopengl32
/tmp/ccec30zH.o:conftest.c:(.text+0xc): undefined reference to `wglCreateContext'

conftest.c:

#ifdef __cplusplus
extern "C"
#endif
char wglCreateContext ();
int
main ()
{
return wglCreateContext ();
  ;
  return 0;
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