Comment # 5 on bug 1121391 from Charles Arnold

(In reply to Jan Beulich from comment #3)
> I can't reproduce the -Werror=address-of-packed-member errors (with a gcc
> build from mid of December last year). Does the RPM build force any warnings
> on that a non-RPM build would not enable?


Here is the gcc command for the debug build for e820.c

gcc -m64 -DBUILD_ID -fno-strict-aliasing -std=gnu99 -Wall -Wstrict-prototypes
-Wdeclaration-after-statement -Wno-unused-but-set-variable
-Wno-unused-local-typedefs   -O1 -fno-omit-frame-pointer -nostdinc -fno-builtin
-fno-common -Werror -Wredundant-decls -Wno-pointer-arith -Wvla -pipe -D__XEN__
-include
/home/abuild/rpmbuild/BUILD/xen-4.12.0-testing/xen/include/xen/config.h
'-D__OBJECT_FILE__="e820.o"' -Wa,--strip-local-absolute -g -MMD -MF ./.e820.o.d
-DXEN_BUILD_EFI  -I/home/abuild/rpmbuild/BUILD/xen-4.12.0-testing/xen/include
-I/home/abuild/rpmbuild/BUILD/xen-4.12.0-testing/xen/include/asm-x86/mach-generic
-I/home/abuild/rpmbuild/BUILD/xen-4.12.0-testing/xen/include/asm-x86/mach-default
-DXEN_IMG_OFFSET=0x200000 '-D__OBJECT_LABEL__=arch$x86$e820.o' -msoft-float
-fno-stack-protector -fno-exceptions -Wnested-externs -DHAVE_AS_VMX
-DHAVE_AS_SSE4_2 -DHAVE_AS_EPT -DHAVE_AS_RDRAND -DHAVE_AS_FSGSBASE
-DHAVE_AS_RDSEED -U__OBJECT_LABEL__ -DHAVE_AS_QUOTED_SYM
'-D__OBJECT_LABEL__=arch/x86/e820.o' -DHAVE_AS_INVPCID -DHAVE_AS_NEGATIVE_TRUE
-DHAVE_AS_NOPS_DIRECTIVE -mno-red-zone -fpic -fno-asynchronous-unwind-tables
-mno-sse -mskip-rax-setup -DGCC_HAS_VISIBILITY_ATTRIBUTE
-mindirect-branch=thunk-extern -mindirect-branch-register
-DCONFIG_INDIRECT_THUNK -fno-jump-tables
-Wa,-I/home/abuild/rpmbuild/BUILD/xen-4.12.0-testing/xen/include -DBUILD_ID_EFI
-c e820.c -o e820.o

The only difference in flags between the debug and non debug are,
Debug: -O1 -fno-omit-frame-pointer -g
Non-Debug: -O2 -fomit-frame-pointer