Compiler Support

This table summarizes how the supported compilers interact with the variables described on Configure-Time and project-local.cmake: How To Hook Into LIBRA. The variables in the table are an attempt at a polymorphic interface for supporting different compilers, cmake style. In the compiler-specific sections that follow, the shown variables have suffixes ({_GNU,_CLANG,_INTEL}) which are pure to get the docs to link unambiguously and are not present in the code.

LIBRA Variable	gcc/g++	clang/clang++	icx/icpx
`LIBRA_DEBUG_INFO`	Yes	Yes	Yes
`LIBRA_BUILD_PROF`	No	Yes	No
`LIBRA_FORTIFY`	Yes	Yes	No
`LIBRA_LTO`	Yes, via cmake builtin	Yes, via cmake builtin	Yes, via cmake builtin
`LIBRA_OPT_LEVEL`	Yes	Yes	Yes
`LIBRA_NATIVE_OPT`	Yes	Yes	Yes
`LIBRA_C_DIAG_CANDIDATES`	Yes	Yes	Yes
`LIBRA_CXX_DIAG_CANDIDATES`	Yes	Yes	Yes
`LIBRA_SAN`	Yes, all types	Yes, all types	Yes, all types
`LIBRA_PGO`	Yes	Yes	Yes
`LIBRA_CODE_COV`	Yes	Yes	No
`LIBRA_VALGRIND_COMPAT`	Yes	Yes	No
`LIBRA_STDLIB`	Yes	Yes	Yes

GNU (gcc/g++)

LIBRA_DEBUG_INFO_GNU: If enabled: -g2. If disabled: -g0.

LIBRA_FORTIFY_GNU

If STACK: -fstack-protector.

If SOURCE: -D_FORTIFY_SOURCE=2.

If GOT: -Wl,-z,relro -Wl,-z,now.

If FORMAT: -Wformat-security -Werror=format=2.

LIBRA_OPT_LEVEL_GNU

Set to -O0 on Debug builds and -O3 on release builds, unless overriden.

LIBRA_NATIVE_OPT_GNU

If enabled: -march=native -mtune=native.

LIBRA_SAN_GNU

If MSAN enabled:

-fno-omit-frame-pointer
-fno-optimize-sibling-calls
-fsanitize=leak
-fsanitize-recover=all

If ASAN is enabled:

-fno-omit-frame-pointer
-fno-optimize-sibling-calls
-fsanitize=address
-fsanitize-address-use-after-scope
-fsanitize=pointer-compare
-fsanitize=pointer-subtract
-fsanitize-recover=all

If SSAN is enabled:

-fno-omit-frame-pointer
-fstack-protector-all
-fstack-protector-strong
-fsanitize-recover=all.

If UBSAN is enabled:

-fno-omit-frame-pointer
-fsanitize=undefined
-fsanitize=float-divide-by-zero
-fsanitize=float-cast-overflow
-fsanitize=null
-fsanitize=signed-integer-overflow
-fsanitize=bool
-fsanitize=enum
-fsanitize=builtin
-fsanitize=bounds
-fsanitize=vptr
-fsanitize=pointer-overflow
-fsanitize-recover=all

If TSAN is enabled:

-fno-omit-frame-pointer
-fsanitize=thread
-fsanitize-recover=all

LIBRA_PGO_GNU

If GEN: -fprofile-generate.

If USE: -fprofile-use.

LIBRA_CODE_COV_CLANG

If enabled: -fprofile-arcs -ftest-coverage -fno-inline -fprofile-update=atomic.

LIBRA_VALGRIND_COMPAT_CLANG

If enabled: -mno-sse3.

LIBRA_STDLIB_GNU

If NONE: -nostdlib.

If STDCXX: N/A.

If CXX: N/A.

clang (clang/clang++)

LIBRA_DEBUG_INFO_CLANG

If enabled: -g2. If disabled: -g0.

LIBRA_BUILD_PROF_CLANG

If enabled: -ftime-trace.

LIBRA_FORTIFY_CLANG

If STACK: -fstack-protector.

If SOURCE: -D_FORTIFY_SOURCE=2.

If GOT: -Wl,-z,relro -Wl,-z,now.

If FORMAT: -Wformat-security -Werror=format=2.

LIBRA_OPT_LEVEL_CLANG

Set to -O0 on Debug builds and -O3 on release builds, unless overriden.

LIBRA_SAN_GNU

If MSAN enabled:

-fno-omit-frame-pointer
-fno-optimize-sibling-calls
fsanitize=memory
-fsanitize-memory-track-origins

If ASAN is enabled:

-fno-omit-frame-pointer
-fno-optimize-sibling-calls
-fsanitize=address,leak

If SSAN is enabled:

-fno-omit-frame-pointer
-fstack-protector-all
-fstack-protector-strong
-fsanitize=safe-stack

If UBSAN is enabled:

-fno-omit-frame-pointer
-fsanitize=undefined
-fsanitize=float-divide-by-zero
-fsanitize=unsigned-integer-overflow
-fsanitize=local-bounds
-fsanitize=nullability

If TSAN is enabled:

-fno-omit-frame-pointer -fsanitize=thread

LIBRA_PGO_CLANG

If GEN: -fprofile-generate. Also passed as linker options to ${PROJECT_NAME}`.

If USE: -fprofile-use.

LIBRA_CODE_COV_CLANG

If enabled: -fprofile-instr-generate -fcoverage-mapping -fno-inline.

LIBRA_VALGRIND_COMPAT_CLANG

If enabled: -mno-sse3.

LIBRA_STDLIB_CLANG

If NONE: -nostdlib.

If STDCXX: -stdlib=libstdc++.

If CXX: -stdlib=libc++

Intel LLVM (icx/icpx)

LIBRA_DEBUG_INFO_INTEL: If enabled: -g2. If disabled: -g0.

LIBRA_NATIVE_OPT_INTEL

If enabled: -xHost.

LIBRA_SAN_INTEL

If MSAN enabled:

-fno-omit-frame-pointer
-fno-optimize-sibling-calls
-fsanitize=memory
-fsanitize-memory-track-origins

If ASAN is enabled:

-fno-omit-frame-pointer
-fno-optimize-sibling-calls
-fsanitize=address,leak

If SSAN is enabled:

-fno-omit-frame-pointer
-fstack-protector-all
-fstack-protector-strong
-fstack-security-check

If UBSAN is enabled:

-fno-omit-frame-pointer
-fsanitize=undefined

If TSAN is enabled:

-fno-omit-frame-pointer
-fsanitize=thread

LIBRA_PGO_INTEL

If GEN: -fprofile-generate. Also passed as linker options to ${PROJECT_NAME}`.

If USE: -fprofile-use

This is software PGO. Intel also supports HWPGO experimentally, but it isn’t ready for prime time yet.

LIBRA_STDLIB_GNU

If NONE: -nostdlib.

If STDCXX: -stdlib=libstdc++.

If CXX: -stdlib=libc++