When compiling toolchain with buildroot - gcc ubsan compilation error: ubsan.c: In function ‘bool ubsan_use_new_style_p(location_t)’: ../../gcc/ubsan.c:1474:23: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]

[XVilka]

Compiling on Gentoo, gcc 7.3.0:

/usr/x86_64-pc-linux-gnu/gcc-bin/7.3.0/g++ -fno-PIE -c   -O2 -I/home/xvilka/radare/competition/csky/buildroot/output/host/include -DIN_GCC  -DCROSS_DIRECTORY_STRUCTURE   
-fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long 
-Wno-variadic-macros -Wno-overlength-strings   -DHAVE_CONFIG_H -I. -I. -I../../gcc -I../../gcc/. -I../../gcc/../include -I../../gcc/../libcpp/include 
-I/home/xvilka/radare/competition/csky/buildroot/output/host/include -I/home/xvilka/radare/competition/csky/buildroot/output/host/include 
-I/home/xvilka/radare/competition/csky/buildroot/output/host/include  -I../../gcc/../libdecnumber -I../../gcc/../libdecnumber/dpd -I../libdecnumber -I../../gcc/../libbacktrace   -o 
tree-call-cdce.o -MT tree-call-cdce.o -MMD -MP -MF ./.deps/tree-call-cdce.TPo ../../gcc/tree-call-cdce.c
In file included from ./tm.h:32:0,
                 from ../../gcc/backend.h:28,
                 from ../../gcc/tree-call-cdce.c:24:
../../gcc/config/csky/abiv1_csky.h:866:0: warning: "ASM_APP_ON" redefined
 #define ASM_APP_ON "// inline asm begin\n"
 
In file included from ./tm.h:29:0,
                 from ../../gcc/backend.h:28,
                 from ../../gcc/tree-call-cdce.c:24:
../../gcc/config/gnu-user.h:33:0: note: this is the location of the previous definition
 #define ASM_APP_ON "#APP\n"
 
In file included from ./tm.h:32:0,
                 from ../../gcc/backend.h:28,
                 from ../../gcc/tree-call-cdce.c:24:
../../gcc/config/csky/abiv1_csky.h:867:0: warning: "ASM_APP_OFF" redefined
 #define ASM_APP_OFF "// inline asm end\n"
 
In file included from ./tm.h:29:0,
                 from ../../gcc/backend.h:28,
                 from ../../gcc/tree-call-cdce.c:24:
../../gcc/config/gnu-user.h:36:0: note: this is the location of the previous definition
 #define ASM_APP_OFF "#NO_APP\n"
 
../../gcc/1
       || xloc.file == '\0' || xloc.file[0] == '\xff'
                       ^~~~
make[2]: *** [Makefile:1085: ubsan.o] Error 1
make[2]: *** Waiting for unfinished jobs....
rm gcov-tool.pod cpp.pod gcov.pod gpl.pod gfdl.pod fsf-funding.pod gcc.pod
make[2]: Leaving directory '/home/xvilka/radare/competition/csky/buildroot/output/build/host-gcc-initial-080eee5e337301372ee587b8e7938629fe5e3fb8/build/gcc'
make[1]: *** [Makefile:4113: all-gcc] Error 2
make[1]: Leaving directory '/home/xvilka/radare/competition/csky/buildroot/output/build/host-gcc-initial-080eee5e337301372ee587b8e7938629fe5e3fb8/build'
make: *** [package/pkg-generic.mk:251: /home/xvilka/radare/competition/csky/buildroot/output/build/host-gcc-initial-080eee5e337301372ee587b8e7938629fe5e3fb8/.stamp_built] Error 2

[guoren83]

The problem is from gcc7.3 compile gcc6.3 it's not a C-SKY issue.
Please try in ubuntu 16.04.
You also can download pre-built toolchain from https://gitlab.com/c-sky/buildroot/pipelines

[XVilka]

They fixed it in the later 6.x versions, can you please rebase your code on top of them? https://github.com/gcc-mirror/gcc/blob/gcc-6-branch/gcc/ubsan.c#L1477

[guoren83]

Good idea, I'll push our toolchain guys.