8b6366f875
TianoCore BZ#700 [1] Set the '-Wno-unused-const-variables' in RELEASE builds with the GGC49 and GCC5 toolchain. This fixes the RELEASE build of OVMF with GCC in version 6 or newer. GCC 6 added the '-Wunused-const-variable' warning, which gets activated by '-Wunused-variable' and has the following behavior: "Warn whenever a constant static variable is unused aside from its declaration" [2] Commit2ad6ba80a1introduced a case where exactly this happens on a RELEASE build. All uses of the static const variable are located in debug code only, which gets thrown out by the compiler on RELEASE builds and thus triggers the unused-const-variable warning. There is currently no GCC 6 toolchain target defined and doing so would add a lot of boilerplate code. Instead, use the fact that GCC ignores unknown '-Wno-*' options: "[...] if the -Wno- form is used [...] no diagnostic is produced for -Wno-unknown-warning unless other diagnostics are being produced" This behavior is available in GCC 4.9 [3] (and also earlier, for that matter), so add the flag to the GCC49 and GCC5 toolchain, even if both GCC versions do not supports it. GCC49 doesn't enables LTO whereas GCC5 does. As GCC 6.0 through 6.2 had bugs relating to LTO there can be desire to use the GCC49 target even if compiling with GCC 6, see432f1d83f7. Orient the changes on20d00edf21which moved the '-Wno-unused-but-set-variable' flag to RELEASE builds only, as there it ensure that it does not gets raised if the only usage of a variable is in (then collapsed) debug code. [1] https://bugzilla.tianocore.org/show_bug.cgi?id=700 [2] https://gcc.gnu.org/onlinedocs/gcc-6.4.0/gcc/Warning-Options.html#index-Wunused-const-variable [3] https://gcc.gnu.org/onlinedocs/gcc-4.9.0/gcc/Warning-Options.html Cc: Yonghong Zhu <yonghong.zhu@intel.com> Cc: Liming Gao <liming.gao@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Liming Gao <liming.gao@intel.com> [lersek@redhat.com: fix typo in subject]
EDK II Project
A modern, feature-rich, cross-platform firmware development environment for the UEFI and PI specifications from www.uefi.org.
Contributions to the EDK II open source project are covered by the TianoCore Contribution Agreement 1.1
The majority of the content in the EDK II open source project uses a BSD 2-Clause License. The EDK II open source project contains the following components that are covered by additional licenses:
- AppPkg/Applications/Python/Python-2.7.2/Tools/pybench
- AppPkg/Applications/Python/Python-2.7.2
- AppPkg/Applications/Python/Python-2.7.10
- BaseTools/Source/C/BrotliCompress
- MdeModulePkg/Library/BrotliCustomDecompressLib
- OvmfPkg
- CryptoPkg/Library/OpensslLib/openssl
The EDK II Project is composed of packages. The maintainers for each package are listed in Maintainers.txt.