CMake doesn't fail if no SSL was found (was: undefined reference to `tr_rand_buffer')

[nschloe]

When building transmission master from scratch, I'm getting link errors of the kind

[ 69%] Linking C executable transmission-test-history
libtransmission.a(session.c.o): In function `tr_peerIdInit':
session.c:(.text+0x874): undefined reference to `tr_rand_buffer'
[...]

Getting there:

git clone --recursive git@github.com:transmission/transmission.git ../source-upstream/
cmake ../source-upstream/
make

CMake output:

-- The C compiler identification is GNU 4.9.2
-- The CXX compiler identification is GNU 4.9.2
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Found Git: /usr/bin/git (found version "2.1.4") 
-- Looking for pthread.h
-- Looking for pthread.h - found
-- Looking for pthread_create
-- Looking for pthread_create - not found
-- Looking for pthread_create in pthreads
-- Looking for pthread_create in pthreads - not found
-- Looking for pthread_create in pthread
-- Looking for pthread_create in pthread - found
-- Found Threads: TRUE  
-- Found CURL: /usr/lib/arm-linux-gnueabihf/libcurl.so (found suitable version "7.38.0", minimum required is "7.15.4") 
-- Found ICONV: /usr/lib/arm-linux-gnueabihf/libc.so  
-- Performing Test ICONV_SECOND_ARGUMENT_IS_CONST
-- Performing Test ICONV_SECOND_ARGUMENT_IS_CONST - Failed
-- Could NOT find OpenSSL, try to set the path to OpenSSL root folder in the system variable OPENSSL_ROOT_DIR (missing:  OPENSSL_LIBRARIES OPENSSL_INCLUDE_DIR) (Required is at least version "0.9.7")
-- Could NOT find CyaSSL (missing:  CYASSL_LIBRARY CYASSL_INCLUDE_DIR) (Required is at least version "3.0")
-- Could NOT find PolarSSL (missing:  POLARSSL_LIBRARY POLARSSL_INCLUDE_DIR) (Required is at least version "1.2")
-- Checking for modules 'gtk+-3.0>=3.4.0;glib-2.0>=2.32.0;gio-2.0>=2.26.0;gmodule-2.0>=2.32.0;gthread-2.0>=2.32.0'
--   
-- Found ZLIB: /usr/lib/arm-linux-gnueabihf/libz.so (found suitable version "1.2.8", minimum required is "1.2.3") 
-- Could NOT find EVENT2 (missing:  EVENT2_LIBRARY EVENT2_INCLUDE_DIR) (Required is at least version "2.0.10")
-- Could NOT find NATPMP (missing:  NATPMP_LIBRARY NATPMP_INCLUDE_DIR) 
-- Could NOT find MINIUPNPC (missing:  MINIUPNPC_LIBRARY MINIUPNPC_INCLUDE_DIR MINIUPNPC_API_VERSION) 
-- Could NOT find DHT (missing:  DHT_LIBRARY DHT_INCLUDE_DIR) 
-- Could NOT find UTP (missing:  UTP_LIBRARY UTP_INCLUDE_DIR) 
-- Could NOT find B64 (missing:  B64_LIBRARY B64_INCLUDE_DIR) 
-- Looking for sys/inotify.h
-- Looking for sys/inotify.h - found
-- Looking for inotify_init
-- Looking for inotify_init - found
-- Looking for include files sys/types.h, sys/event.h
-- Looking for include files sys/types.h, sys/event.h - not found
-- Looking for kqueue
-- Looking for kqueue - not found
-- Could NOT find SYSTEMD (missing:  SYSTEMD_LIBRARY SYSTEMD_INCLUDE_DIR) 
-- Performing Test NO_LFS_MACROS_REQUIRED
-- Performing Test NO_LFS_MACROS_REQUIRED - Failed
-- Performing Test FILE_OFFSET_BITS_LFS_MACRO_REQUIRED
-- Performing Test FILE_OFFSET_BITS_LFS_MACRO_REQUIRED - Success
-- Looking for stdbool.h
-- Looking for stdbool.h - found
-- Looking for sys/statvfs.h
-- Looking for sys/statvfs.h - found
-- Looking for xfs/xfs.h
-- Looking for xfs/xfs.h - not found
-- Looking for xlocale.h
-- Looking for xlocale.h - found
-- Looking for libintl.h
-- Looking for libintl.h - found
-- Looking for _configthreadlocale
-- Looking for _configthreadlocale - not found
-- Looking for canonicalize_file_name
-- Looking for canonicalize_file_name - found
-- Looking for daemon
-- Looking for daemon - found
-- Looking for fallocate64
-- Looking for fallocate64 - found
-- Looking for getmntent
-- Looking for getmntent - found
-- Looking for getpagesize
-- Looking for getpagesize - found
-- Looking for htonll
-- Looking for htonll - not found
-- Looking for localtime_r
-- Looking for localtime_r - found
-- Looking for memmem
-- Looking for memmem - found
-- Looking for mkdtemp
-- Looking for mkdtemp - found
-- Looking for ntohll
-- Looking for ntohll - not found
-- Looking for posix_fadvise
-- Looking for posix_fadvise - found
-- Looking for posix_fallocate
-- Looking for posix_fallocate - found
-- Looking for posix_memalign
-- Looking for posix_memalign - found
-- Looking for pread
-- Looking for pread - found
-- Looking for pwrite
-- Looking for pwrite - found
-- Looking for statvfs
-- Looking for statvfs - found
-- Looking for strlcpy
-- Looking for strlcpy - not found
-- Looking for strsep
-- Looking for strsep - found
-- Looking for syslog
-- Looking for syslog - found
-- Looking for uselocale
-- Looking for uselocale - found
-- Looking for valloc
-- Looking for valloc - found
-- Looking for libintl_gettext in intl
-- Looking for libintl_gettext in intl - not found
-- Looking for sqrt in m
-- Looking for sqrt in m - found
-- Looking for socket in c
-- Looking for socket in c - found
-- Looking for gethostbyname in c
-- Looking for gethostbyname in c - found
-- Configuring done
-- Generating done

[nschloe]

Might be a duplicate of the (closed) order #66.

[mikedld]

I noticed from configuration log in #190 that none of crypto backends (OpenSSL, CyaSSL, PolarSSL) were found. Judging by the CMake code, this should have resulted in FATAL_ERROR message but didn't for some reason.

I'll take a look in the evening. Meanwhile, you need to reconfigure so that at least one crypto backend is found.

[nschloe]

That works, thanks.

[yolanjoy]

I had this exact problem on Ubuntu 16.04. I had to install libssl-dev and the compilation completed successfully.