chore(cmake): drop FORTIFY_SOURCE=2 from release builds.

It causes weird issues with zig finding the prototypes for `strlcat` and `strlcpy` in
`lib/libc/include/generic-glibc/bits/string_fortified.h`,
but their implementation is not present, leading to link time build failure.
This means:
* check_symbol_exists(strlcpy "string.h" HAVE_STRLCPY) fails
* `HAVE_STRLCPY` and `HAVE_STRLCAT` are not defined
* `<libscap/strl.h>` defines both `strlcat` and `strlcpy`
* but `string.h` included at the start of `strl.h` will find the prototypes, thus failing because of symbol redefinition

Signed-off-by: Federico Di Pierro <[email protected]>

Author: FedeDP

cmake/modules/CompilerFlags.cmake

@@ -48,11 +48,6 @@ endif()
 
 
 if(NOT MSVC)
-
-	if(CMAKE_BUILD_TYPE STREQUAL "release")
-		set(FALCO_SECURITY_FLAGS "${FALCO_SECURITY_FLAGS} -D_FORTIFY_SOURCE=2")
-	endif()
-
 	if(USE_ASAN)
 		set(FALCO_SECURITY_FLAGS "${FALCO_SECURITY_FLAGS} -fsanitize=address")
 	endif()
@@ -74,8 +69,8 @@ if(NOT MSVC)
 		set(CMAKE_COMMON_FLAGS "${CMAKE_COMMON_FLAGS} -Wextra ${CMAKE_SUPPRESSED_WARNINGS}")
 	endif()
 
-	set(CMAKE_C_FLAGS "${CMAKE_COMMON_FLAGS}")
-	set(CMAKE_CXX_FLAGS "-std=c++17 ${CMAKE_COMMON_FLAGS}")
+	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${CMAKE_COMMON_FLAGS}")
+	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++17 ${CMAKE_COMMON_FLAGS}")
 
 	set(CMAKE_C_FLAGS_DEBUG "${FALCO_EXTRA_DEBUG_FLAGS}")
 	set(CMAKE_CXX_FLAGS_DEBUG "${FALCO_EXTRA_DEBUG_FLAGS}")

cmake/modules/falcosecurity-libs.cmake

@@ -56,7 +56,6 @@ set(LIBS_PACKAGE_NAME "falcosecurity")
 
 if(CMAKE_SYSTEM_NAME MATCHES "Linux")
   add_definitions(-D_GNU_SOURCE)
-  add_definitions(-DHAS_CAPTURE)
 endif()
 
 if(MUSL_OPTIMIZED_BUILD)