Sadly, that always happens to me. Haven't debugged but worked around it. Open configure.ac, remove the pkg_config check for libcurl, open Makefile.am, and replace @LIBCURL_FLAGS@ or whatever the keyword is with direct paths to the library directory where libcurl.a resides and add -lcurl then.
OK, gotcha. I actually found after fooling around some that if you comment the lines thus:
#PKG_CHECK_MODULES([LIBCURL], [libcurl >= 7.15.6], [AC_DEFINE([CURL_HAS_SOCKOPT], [1], [Defined if version of curl supports sockopts.])],
#[PKG_CHECK_MODULES([LIBCURL], [libcurl >= 7.10.1], ,[AC_MSG_ERROR([Missing required libcurl dev >= 7.10.1])])])
#AC_SUBST(LIBCURL_LIBS)
and add the line:
LIBCURL_LIBS=-lcurl
you don't have to change Makefile.am
Of course now it's bitching about include files in the Platform SDK.
I can't even tell you exactly what I had to do to fix it coz I just kept hacking at the configure and Makefile until it worked.
Then, oddly, it worked fine so I kept that configure.ac file and have done the same change to it every time needed.
Running a diff now it looks like the ONLY thing I did was comment out the first two lines you listed (not the 3rd) and all was OK after that.
Hard to tell if there was anything special in the Makefile, but Makefile's aren't that difficult to mess with, whereas I knew very little about a configure.ac when I started down the path to hell known as mingw32
