Created attachment 1253359 [details]
build.log

Created attachment 1253360 [details]
root.log

Created attachment 1253361 [details]
state.log

the build.log extract is pointing to a line in skiboot.h
But I do not understand what is wrong with it.

=== extract build.log
gcc        -I/builddir/build/BUILD/skiboot-skiboot-5.2.0/include -Iinclude -MMD -include /builddir/build/BUILD/skiboot-skiboot-5.2.0/include/config.h -I/builddir/build/BUILD/skiboot-skiboot-5.2.0/libfdt -I/builddir/build/BUILD/skiboot-skiboot-5.2.0/libflash -I/builddir/build/BUILD/skiboot-skiboot-5.2.0/libc/include -I/builddir/build/BUILD/skiboot-skiboot-5.2.0 -I/builddir/build/BUILD/skiboot-skiboot-5.2.0/libpore -D__HAVE_LIBPORE__ -D__SKIBOOT__ -nostdinc -isystem /usr/lib/gcc/ppc64le-redhat-linux/7/include -DBITS_PER_LONG=64 -DHAVE_BIG_ENDIAN -ffreestanding -fno-strict-aliasing -fstack-protector-all -pie -mbig-endian -m64 -Wl,--oformat,elf64-powerpc -mabi=elfv1 -std=gnu11 -fstack-protector -fstack-protector-strong -Wjump-misses-init -Wsuggest-attribute=const -Wsuggest-attribute=noreturn -Wstack-usage=1024 -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -Werror-implicit-function-declaration -Wdeclaration-after-statement -Wno-pointer-sign -Wextra -Wno-sign-compare -Wmissing-prototypes -Wmissing-declarations -Wwrite-strings -Wcast-align -Winit-self -Wframe-larger-than=1024 -Werror -Os -ffunction-sections -g -msoft-float -mno-string -mno-multiple -mno-vsx -mno-direct-move -mno-altivec  -c hw/phb3.c -o hw/phb3.o
In file included from hw/p7ioc-phb.c:17:0:
hw/p7ioc-phb.c: In function 'p7ioc_sm_slot_power_off':
/builddir/build/BUILD/skiboot-skiboot-5.2.0/include/skiboot.h:107:31: error: this statement may fall through [-Werror=implicit-fallthrough=]
 #define prlog(l, f, ...) do { _prlog(l, pr_fmt(f), ##__VA_ARGS__); } while(0)
                               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
=== extract of skiboot.h
void _prlog(int log_level, const char* fmt, ...) __attribute__((format (printf, 2, 3)));
#define prlog(l, f, ...) do { _prlog(l, pr_fmt(f), ##__VA_ARGS__); } while(0)
===

Created attachment 1255678 [details]
skiboot_bypass_fallthrough.patch

my suggested patch added as new attachment

(In reply to Michel Normand from comment #5)
> Created attachment 1255678 [details]
> skiboot_bypass_fallthrough.patch
> 
> my suggested patch added as new attachment

note that similar changes already implemented upstream in main branch.

(In reply to Michel Normand from comment #6)
> (In reply to Michel Normand from comment #5)
> > Created attachment 1255678 [details]
> > skiboot_bypass_fallthrough.patch
> > 
> > my suggested patch added as new attachment
> 
> note that similar changes already implemented upstream in main branch.

and completed scatchbuild with above patch 
https://koji.fedoraproject.org/koji/taskinfo?taskID=17970134

This bug appears to have been reported against 'rawhide' during the Fedora 26 development cycle.
Changing version to '26'.

hegdevasant's opal-prd-5.5.0-2.fc27 completed http://koji.fedoraproject.org/koji/buildinfo?buildID=881423

I've built opal-prd for rawhide as well as for fedora 26.

-Vasant

FC 26 build : https://koji.fedoraproject.org/koji/taskinfo?taskID=19076040

Can someone tag this build to next fc26 build?

-Vasant

(In reply to Vasant Hegde from comment #11)
> FC 26 build : https://koji.fedoraproject.org/koji/taskinfo?taskID=19076040
> 
> Can someone tag this build to next fc26 build?
> 
> -Vasant

This is handled in #1414489


Closing this bug.

-Vasant