curl/CMake/OtherTests.cmake
Viktor Szakats 93e6e4b823
cmake: work around ios.toolchain.cmake breaking feature-detections
Fix builds with CMake configured to falsely return successful detection
when using `check_function_exists()` (and `check_library_exists()`, and
anything based on `try_compile()` that's relying on the linker). After
such mis-detection the build fails when trying to use the feature that
doesn't in fact exist.

The mis-detection is caused by this CMake setting:
```
set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
```
It is set by default (or on conditions) when using 3rd-party toolchain:
https://github.com/leetal/ios-cmake/blob/master/ios.toolchain.cmake

After this patch the curl build overrides this setting for the duration
of feature tests, and logs a message about it.

Also preset and skip feature tests for known mis-detections:
- `connect()` in `libsocket`
- `getpass_r()`
- `eventfd()` (did not cause an issue due to a separate bug)
- `sendmmsg()` (did not cause an issue because it's Linux-only)

If mis-detections are still seen, the workaround is to force-set the
specific feature by passing `-DHAVE_*=OFF` to cmake.
Also consider passing `-DENABLE_STRICT_TRY_COMPILE=ON` for
`ios.toolchain.cmake` to fix the root cause.

Interestingly curl itself uses this setting to speed up compile-only
detections: be17f298ff #3744

Also:
- OtherTests.cmake: restore original value of
  `CMAKE_TRY_COMPILE_TARGET_TYPE`. Before this patch it reset it
  to empty.
- OtherTests.cmake: unset a local variable after use, quote a string.

Follow-up to 8e34505776 #15164
Follow-up to 8b76a8aeb2 #15525
Ref: https://github.com/leetal/ios-cmake/issues/47
Ref: https://gitlab.kitware.com/cmake/cmake/-/issues/18121
Ref: https://cmake.org/cmake/help/latest/variable/CMAKE_TRY_COMPILE_TARGET_TYPE.html
Reported-by: Dan Rosser
Fixes #15557
Closes #15559
2024-11-13 10:42:38 +01:00

157 lines
4.7 KiB
CMake

#***************************************************************************
# _ _ ____ _
# Project ___| | | | _ \| |
# / __| | | | |_) | |
# | (__| |_| | _ <| |___
# \___|\___/|_| \_\_____|
#
# Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution. The terms
# are also available at https://curl.se/docs/copyright.html.
#
# You may opt to use, copy, modify, merge, publish, distribute and/or sell
# copies of the Software, and permit persons to whom the Software is
# furnished to do so, under the terms of the COPYING file.
#
# This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
# KIND, either express or implied.
#
# SPDX-License-Identifier: curl
#
###########################################################################
include(CheckCSourceCompiles)
include(CheckCSourceRuns)
include(CheckTypeSize)
macro(add_header_include _check _header)
if(${_check})
set(_source_epilogue "${_source_epilogue}
#include <${_header}>")
endif()
endmacro()
set(_cmake_try_compile_target_type_save ${CMAKE_TRY_COMPILE_TARGET_TYPE})
set(CMAKE_TRY_COMPILE_TARGET_TYPE "STATIC_LIBRARY")
if(NOT DEFINED HAVE_STRUCT_SOCKADDR_STORAGE)
cmake_push_check_state()
unset(CMAKE_EXTRA_INCLUDE_FILES)
if(WIN32)
set(CMAKE_EXTRA_INCLUDE_FILES "winsock2.h")
set(CMAKE_REQUIRED_LIBRARIES "ws2_32")
elseif(HAVE_SYS_SOCKET_H)
set(CMAKE_EXTRA_INCLUDE_FILES "sys/socket.h")
endif()
check_type_size("struct sockaddr_storage" SIZEOF_STRUCT_SOCKADDR_STORAGE)
set(HAVE_STRUCT_SOCKADDR_STORAGE ${HAVE_SIZEOF_STRUCT_SOCKADDR_STORAGE})
cmake_pop_check_state()
endif()
if(NOT WIN32)
set(_source_epilogue "#undef inline")
add_header_include(HAVE_SYS_TYPES_H "sys/types.h")
add_header_include(HAVE_SYS_SOCKET_H "sys/socket.h")
check_c_source_compiles("${_source_epilogue}
int main(void)
{
int flag = MSG_NOSIGNAL;
(void)flag;
return 0;
}" HAVE_MSG_NOSIGNAL)
endif()
set(_source_epilogue "#undef inline")
add_header_include(HAVE_SYS_TIME_H "sys/time.h")
check_c_source_compiles("${_source_epilogue}
#include <time.h>
int main(void)
{
struct timeval ts;
ts.tv_sec = 0;
ts.tv_usec = 0;
(void)ts;
return 0;
}" HAVE_STRUCT_TIMEVAL)
set(CMAKE_TRY_COMPILE_TARGET_TYPE ${_cmake_try_compile_target_type_save})
unset(_cmake_try_compile_target_type_save)
# Detect HAVE_GETADDRINFO_THREADSAFE
if(WIN32)
set(HAVE_GETADDRINFO_THREADSAFE ${HAVE_GETADDRINFO})
elseif(NOT HAVE_GETADDRINFO)
set(HAVE_GETADDRINFO_THREADSAFE FALSE)
elseif(APPLE OR
CMAKE_SYSTEM_NAME STREQUAL "AIX" OR
CMAKE_SYSTEM_NAME STREQUAL "FreeBSD" OR
CMAKE_SYSTEM_NAME STREQUAL "HP-UX" OR
CMAKE_SYSTEM_NAME STREQUAL "MidnightBSD" OR
CMAKE_SYSTEM_NAME STREQUAL "NetBSD" OR
CMAKE_SYSTEM_NAME STREQUAL "SunOS")
set(HAVE_GETADDRINFO_THREADSAFE TRUE)
elseif(BSD OR CMAKE_SYSTEM_NAME MATCHES "BSD")
set(HAVE_GETADDRINFO_THREADSAFE FALSE)
endif()
if(NOT DEFINED HAVE_GETADDRINFO_THREADSAFE)
set(_source_epilogue "#undef inline")
add_header_include(HAVE_SYS_SOCKET_H "sys/socket.h")
add_header_include(HAVE_SYS_TIME_H "sys/time.h")
add_header_include(HAVE_NETDB_H "netdb.h")
check_c_source_compiles("${_source_epilogue}
int main(void)
{
#ifdef h_errno
return 0;
#else
#error force compilation error
#endif
}" HAVE_H_ERRNO)
if(NOT HAVE_H_ERRNO)
check_c_source_compiles("${_source_epilogue}
int main(void)
{
h_errno = 2;
return h_errno != 0 ? 1 : 0;
}" HAVE_H_ERRNO_ASSIGNABLE)
if(NOT HAVE_H_ERRNO_ASSIGNABLE)
check_c_source_compiles("${_source_epilogue}
int main(void)
{
#if defined(_POSIX_C_SOURCE) && (_POSIX_C_SOURCE >= 200809L)
return 0;
#elif defined(_XOPEN_SOURCE) && (_XOPEN_SOURCE >= 700)
return 0;
#else
#error force compilation error
#endif
}" HAVE_H_ERRNO_SBS_ISSUE_7)
endif()
endif()
if(HAVE_H_ERRNO OR HAVE_H_ERRNO_ASSIGNABLE OR HAVE_H_ERRNO_SBS_ISSUE_7)
set(HAVE_GETADDRINFO_THREADSAFE TRUE)
endif()
endif()
if(NOT WIN32 AND NOT DEFINED HAVE_CLOCK_GETTIME_MONOTONIC_RAW)
set(_source_epilogue "#undef inline")
add_header_include(HAVE_SYS_TYPES_H "sys/types.h")
add_header_include(HAVE_SYS_TIME_H "sys/time.h")
check_c_source_compiles("${_source_epilogue}
#include <time.h>
int main(void)
{
struct timespec ts;
(void)clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
return 0;
}" HAVE_CLOCK_GETTIME_MONOTONIC_RAW)
endif()
unset(_source_epilogue)