Hello Aaron Durbin, Patrick Rudolph, build bot (Jenkins), Patrick Georgi, Martin Roth,
I'd like you to reexamine a change. Please visit
https://review.coreboot.org/c/coreboot/+/32027
to look at the new patch set (#10).
Change subject: Make common macros double-evaluation safe ......................................................................
Make common macros double-evaluation safe
I just got hit by a double-evaluation bug again, it's time to attempt to fix this once more. Unfortunately there are several issues that don't make this easy:
- bitfield variables don't support typeof() - local macro variables that shadow others trigger -Werror=shadow - sign warnings with integer literal and unsigned var in typeof-MIN() - ({ statement expressions }) can not be used outside functions - romcc doesn't support any of the fancy GCC/clang extensions
This patch tries to address all of them as far as possible with macro magic. We don't have the technology to solve the bitfield and non-function context issues yet (__builtin_choose_expr() still throws a "no statement expression outside a function" error if it's only in the branch that's not chosen, unfortunately), so we'll have to provide alternative macros for use in those cases (and we'll avoid making __ALIGN_MASK() double-evaluation safe for now, since it would be annoying to do that there and having an alignment mask with side effects seems very unlikely). romcc can continue using unsafe versions since we're hopefully not writing a lot of new code for it. Sign warnings can be avoided in literal/variable comparisons by always using the type of the variable there. Shadowing is avoided by picking very explicit local variable names and using a special __COUNTER__ solution for MIN() and MAX() (the only ones of these you're likely to nest).
Also add DIV_ROUND_UP() to libpayload since it's a generally quite useful thing to have.
Change-Id: Iea35156c9aa9f6f2c7b8f00991418b746f44315d Signed-off-by: Julius Werner jwerner@chromium.org --- M payloads/libpayload/include/compiler.h M payloads/libpayload/include/libpayload.h M src/commonlib/include/commonlib/compiler.h M src/commonlib/include/commonlib/helpers.h M src/vendorcode/amd/agesa/f12/Proc/GNB/Gfx/GfxGmcInit.c M src/vendorcode/amd/agesa/f14/Proc/GNB/Gfx/GfxGmcInit.c M src/vendorcode/amd/agesa/f15tn/Proc/GNB/Modules/GnbInitTN/GfxGmcInitTN.c M src/vendorcode/intel/edk2/UDK2015/MdePkg/Include/Base.h M src/vendorcode/intel/edk2/UDK2017/MdePkg/Include/Base.h M src/vendorcode/intel/edk2/uefi_2.4/MdePkg/Include/Base.h 10 files changed, 141 insertions(+), 46 deletions(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/27/32027/10