build: Support for 32 bit linux builds and gcc 4.9 (getsentry#291)

CMakeLists.txt

@@ -39,6 +39,15 @@ if(MSVC)
 	option(SENTRY_BUILD_RUNTIMESTATIC "Build sentry-native with static runtime" OFF)
 endif()
 
+if(LINUX)
+	option(SENTRY_BUILD_FORCE32 "Force a 32bit compile on a 64bit host" OFF)
+	if(SENTRY_BUILD_FORCE32)
+		set(CMAKE_C_FLAGS    "${CMAKE_C_FLAGS} -m32 -D_FILE_OFFSET_BITS=64 -D_LARGEFILE64_SOURCE")
+		set(CMAKE_CXX_FLAGS  "${CMAKE_CXX_FLAGS} -m32 -D_FILE_OFFSET_BITS=64 -D_LARGEFILE64_SOURCE")
+		set_property(GLOBAL PROPERTY FIND_LIBRARY_USE_LIB64_PATHS OFF)
+	endif()
+endif()
+
 # CMAKE_POSITION_INDEPENDENT_CODE must be set BEFORE adding any libraries (including subprojects)
 if(SENTRY_PIC)
 	set(CMAKE_POSITION_INDEPENDENT_CODE ON)

azure-pipelines.yml

@@ -18,8 +18,8 @@ stages:
           matrix:
             Linux (gcc 7, 32-bit):
               vmImage: "ubuntu-18.04"
-              CC: gcc-7 -m32
-              CXX: g++-7 -m32
+              CC: gcc-7
+              CXX: g++-7
               TEST_X86: 1
             Linux (gcc 9):
               vmImage: "ubuntu-latest"

tests/__init__.py

@@ -102,6 +102,8 @@ def cmake(cwd, targets, options=None):
         configcmd.append("-D{}={}".format(key, value))
     if sys.platform == "win32" and os.environ.get("TEST_X86"):
         configcmd.append("-AWin32")
+    elif sys.platform == "linux" and os.environ.get("TEST_X86"):
+        configcmd.append("-DSENTRY_BUILD_FORCE32=ON")
 
     cmakelists_dir = os.path.dirname(os.path.dirname(os.path.realpath(__file__)))
     configcmd.append(cmakelists_dir)

tests/unit/CMakeLists.txt

@@ -46,6 +46,7 @@ target_include_directories(sentry_test_unit PRIVATE
 target_link_libraries(sentry_test_unit PRIVATE
 	${SENTRY_LINK_LIBRARIES}
 	${SENTRY_INTERFACE_LINK_LIBRARIES}
+	"$<$<PLATFORM_ID:Linux>:rt>"
 )
 
 if(MINGW)