使用cmake从源代码构建SQLite3不起作用

Question

我正在 Linux Fedora 39 上工作。我对使用 cmake 很陌生，尽管第一个好的 cmake exirsize 是从源代码构建 sqlite3。

我从官方sqlite站点下载了sqlite3.c和sqlite3.h源文件。我想将源代码编译为 .o（对象）文件，以便稍后可以将其链接到我的主应用程序。运行 cmake 不会出现错误，然后运行它生成的 make 文件不会出现错误，并表示构建已完成，但是当我查看目录时，没有 .o 文件的迹象，也没有任何已编译文件的迹象.

我知道 cmake 文件中使用的某些方法可能不是必需的（例如使用 globbing），但正如我所说，我仍在使用 cmake，看看什么对我有用并适合我未来的项目要求。

我的cmake文件：

cmake_minimum_required(VERSION 3.27)

project(SQLite3
    VERSION 3.0
    DESCRIPTION "SQLite3 source code"
    LANGUAGES C)

# Specify your source directories
set(SOURCE_DIRS 
    "../source" )

# Initialize an empty list to hold all source files
set(SOURCES "")

# Set the output directory for object files
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}")

# Use globbing to include source files from each directory
foreach(SOURCE_DIR ${SOURCE_DIRS})
    file(GLOB_RECURSE DIR_SOURCES 
        "${SOURCE_DIR}/*.cpp"         
        "${SOURCE_DIR}/*.c" 
        "${SOURCE_DIR}/*.cxx")
    list(APPEND SOURCES ${DIR_SOURCES})
endforeach()

# Add the source files to the executable target
add_library(SQLite3 OBJECT ${SOURCES})

# ******I realise this might not be required for this case, but I tried it in any case**************
# Include the directory containing sqlite3.h if necessary
target_include_directories(SQLite3 PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/../headers")

# Set compiler flags based on OS
if (CMAKE_SYSTEM_NAME STREQUAL "Linux")
    # Add compile flags before compiling
    target_compile_options(SQLite3 PRIVATE 
        -Wall -Wextra -O2 -fPIC)
elseif (CMAKE_SYSTEM_NAME STREQUAL "Windows")
    # Add compile flags before compiling
    target_compile_options(SQLite3 PRIVATE 
        -Wall -Wextra -O2 -fPIC)
elseif (CMAKE_SYSTEM_NAME STREQUAL "Darwin")
    # Add compile flags before compiling
    target_compile_options(SQLite3 PRIVATE 
        -Wall -Wextra -O2 -fPIC)
endif()

# Set the version of the compiler
target_compile_features(SQLite3 PRIVATE c_std_11)

我的文件结构：

注意，在生成以下输出时，我确保删除了所有生成的 cmake 文件和文件夹，以确保它是新输出，就像第一次运行一样。

Cmake 控制台输出：

-- The C compiler identification is GNU 13.2.1
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/cc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Configuring done (0.1s)
-- Generating done (0.0s)
-- Build files have been written to: /home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/build

Cmake MakeFile 控制台输出：

[100%] Building C object CMakeFiles/SQLite3.dir/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c.o
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c: In function ‘sqlite3VdbeExec’:
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:96200:50: warning: this statement may fall through [-Wimplicit-fallthrough=]
96200 |                    zPayload[6] = (u8)(v&0xff); v >>= 8;
      |                                                ~~^~~~~
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:96201:11: note: here
96201 |           case 6:  zPayload[5] = (u8)(v&0xff); v >>= 8;
      |           ^~~~
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:96202:50: warning: this statement may fall through [-Wimplicit-fallthrough=]
96202 |                    zPayload[4] = (u8)(v&0xff); v >>= 8;
      |                                                ~~^~~~~
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:96203:11: note: here
96203 |           case 4:  zPayload[3] = (u8)(v&0xff); v >>= 8;
      |           ^~~~
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:96203:50: warning: this statement may fall through [-Wimplicit-fallthrough=]
96203 |           case 4:  zPayload[3] = (u8)(v&0xff); v >>= 8;
      |                                                ~~^~~~~
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:96204:11: note: here
96204 |           case 3:  zPayload[2] = (u8)(v&0xff); v >>= 8;
      |           ^~~~
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:96204:50: warning: this statement may fall through [-Wimplicit-fallthrough=]
96204 |           case 3:  zPayload[2] = (u8)(v&0xff); v >>= 8;
      |                                                ~~^~~~~
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:96205:11: note: here
96205 |           case 2:  zPayload[1] = (u8)(v&0xff); v >>= 8;
      |           ^~~~
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:96205:50: warning: this statement may fall through [-Wimplicit-fallthrough=]
96205 |           case 2:  zPayload[1] = (u8)(v&0xff); v >>= 8;
      |                                                ~~^~~~~
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:96206:11: note: here
96206 |           case 1:  zPayload[0] = (u8)(v&0xff);
      |           ^~~~
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c: In function ‘jsonTranslateTextToBlob’:
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:205078:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
205078 |     if( strncmp(z+i,"null",4)==0 && !sqlite3Isalnum(z[i+4]) ){
       |       ^
/home/rikus/Documents/git_projects/CPP-Project/libraries/sqlite/core/source/sqlite3.c:205084:3: note: here
205084 |   default: {
       |   ^~~~~~~
[100%] Built target SQLite3

所以基本上，根据输出，目标文件现在应该存在于我的构建目录中，但事实并非如此，我也使用文件资源管理器进行了检查。我什至尝试使用一些生成的代码来为我执行此操作，但我得到与上面完全相同的结果。

预先感谢您提供的任何帮助。

Answer 1

来自

add_library

文档...

默认情况下，库文件将在与调用命令的源树目录相对应的构建树目录中创建。

您没有在 makefile 中指定构建目录，并且可能在调用 cmake 时也没有指定，因此它构建在源目录中。

如果您想在其他地方构建，请搜索“out of source build”。