https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78654
Bug ID: 78654
Summary: ubsan can lead to excessive stack usage
Product: gcc
Version: 7.0
URL: https://bugs.linaro.org/show_bug.cgi?id=2350
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: other
Assignee: unassigned at gcc dot gnu.org
Reporter: clyon at gcc dot gnu.org
Target Milestone: ---
[Forwarding Arnd's bug report from
https://bugs.linaro.org/show_bug.cgi?id=2350]
When building the kernel with all sanitizers enabled, some functions have a
much larger stack frame than expected. In some cases we just barely cross the
1024 byte stack size limit for functions that were already using a lot, but one
file sticks out from using almost twice as much as before.
Using today's trunk
$ arm-none-linux-gnueabi-gcc -O2 -Wno-pointer-sign -Wframe-larger-than=100 -
c serpent_generic.i
frame size 528
$ arm-none-linux-gnueabi-gcc -O2 -Wno-pointer-sign -Wframe-larger-than=1024 -c
serpent_generic.i -fsanitize=shift -fsanitize=integer-divide-by-zero
-fsanitize=unreachable -fsanitize=vla-bound -fsanitize=null
-fsanitize=signed-integer-overflow -fsanitize=bounds -fsanitize=object-size
-fsanitize=returns-nonnull-attribute -fsanitize=bool -fsanitize=enum
-fsanitize=alignment
frame size 1072
$ arm-none-linux-gnueabi-gcc -Wall -Wframe-larger-than=100 -Wno-pointer-sign
-Os -c mb86a16.i
frame size 416
$ arm-none-linux-gnueabi-gcc -Wall -Wframe-larger-than=100 -Wno-pointer-sign
-Os -c mb86a16.i -fsanitize=signed-integer-overflow
frame size 448
