Re: Lists and aliasing (Re: Freeze on 27 February)

[Lennart Sorensen]

On Wed, Feb 22, 2012 at 05:50:31PM +0100, Vladimir 'φ-coder/phcoder' Serbinenko 
wrote:
> === modified file 'conf/Makefile.common'
> --- conf/Makefile.common      2012-02-22 15:27:39 +0000
> +++ conf/Makefile.common      2012-02-22 16:29:31 +0000
> @@ -104,7 +104,7 @@
>  CFLAGS_GCRY = -Wno-error -Wno-missing-field-initializers
>  CPPFLAGS_GCRY = -I$(top_srcdir)/grub-core/lib/libgcrypt_wrap
>  
> -CFLAGS_GNULIB = -Wno-undef -Wno-sign-compare -Wno-unused 
> -Wno-unused-parameter -Wno-redundant-decls -Wno-unreachable-code 
> -Wno-conversion -Wno-old-style-definition
> +CFLAGS_GNULIB = -Wno-undef -Wno-sign-compare -Wno-unused 
> -Wno-unused-parameter -Wno-redundant-decls -Wno-unreachable-code 
> -Wno-conversion -Wno-old-style-definition -Wno-unsafe-loop-optimisations
>  CPPFLAGS_GNULIB = -I$(top_builddir)/grub-core/gnulib 
> -I$(top_srcdir)/grub-core/gnulib
>  
>  CFLAGS_POSIX = -fno-builtin
> 
> === modified file 'configure.ac'
> --- configure.ac      2012-02-22 03:56:45 +0000
> +++ configure.ac      2012-02-22 16:32:32 +0000
> @@ -377,7 +377,7 @@
>  LIBS=""
>  
>  # debug flags.
> -WARN_FLAGS="-Wall -W -Wshadow -Wold-style-declaration -Wold-style-definition 
> -Wpointer-arith -Wundef -Wextra -Waddress -Warray-bounds -Wattributes 
> -Wbuiltin-macro-redefined -Wcast-align -Wchar-subscripts -Wclobbered 
> -Wcomment -Wcoverage-mismatch -Wdeprecated -Wdeprecated-declarations 
> -Wdisabled-optimization -Wdiv-by-zero -Wempty-body -Wendif-labels 
> -Wfloat-equal -Wformat-contains-nul -Wformat-extra-args -Wformat-security 
> -Wformat-y2k -Wignored-qualifiers -Wimplicit -Wimplicit-function-declaration 
> -Wimplicit-int -Winit-self -Wint-to-pointer-cast -Winvalid-pch 
> -Wunsafe-loop-optimizations -Wlogical-op -Wmain -Wmissing-braces 
> -Wmissing-field-initializers -Wmissing-format-attribute -Wmissing-noreturn 
> -Wmudflap -Wmultichar -Wnonnull -Woverflow -Wpacked-bitfield-compat 
> -Wparentheses -Wpointer-arith -Wpointer-to-int-cast -Wreturn-type 
> -Wsequence-point -Wshadow -Wsign-compare -Wstrict-aliasing -Wswitch 
> -Wsync-nand -Wtrigraphs  -Wtype-limits -Wundef -Wuninitialized 
> -Wunknown-pragmas -Wunused -Wunused-function -Wunused-label 
> -Wunused-parameter -Wunused-value  -Wunused-variable -Wvariadic-macros 
> -Wvolatile-register-var -Wwrite-strings -Wmissing-declarations 
> -Wmissing-parameter-type  -Wmissing-prototypes -Wnested-externs 
> -Wstrict-prototypes -Wpointer-sign"
> +WARN_FLAGS="-Wall -W -Wshadow -Wold-style-declaration -Wold-style-definition 
> -Wpointer-arith -Wundef -Wextra -Waddress -Warray-bounds -Wattributes 
> -Wbuiltin-macro-redefined -Wcast-align -Wchar-subscripts -Wclobbered 
> -Wcomment -Wcoverage-mismatch -Wdeprecated -Wdeprecated-declarations 
> -Wdisabled-optimization -Wdiv-by-zero -Wempty-body -Wendif-labels 
> -Wfloat-equal -Wformat-contains-nul -Wformat-extra-args -Wformat-security 
> -Wformat-y2k -Wignored-qualifiers -Wimplicit -Wimplicit-function-declaration 
> -Wimplicit-int -Winit-self -Wint-to-pointer-cast -Winvalid-pch 
> -Wunsafe-loop-optimizations -Wlogical-op -Wmain -Wmissing-braces 
> -Wmissing-field-initializers -Wmissing-format-attribute -Wmissing-noreturn 
> -Wmudflap -Wmultichar -Wnonnull -Woverflow -Wpacked-bitfield-compat 
> -Wparentheses -Wpointer-arith -Wpointer-to-int-cast -Wreturn-type 
> -Wsequence-point -Wshadow -Wsign-compare -Wstrict-aliasing -Wswitch 
> -Wsync-nand -Wtrigraphs  -Wtype-limits -Wundef -Wuninitialized 
> -Wunknown-pragmas -Wunused -Wunused-function -Wunused-label 
> -Wunused-parameter -Wunused-value  -Wunused-variable -Wvariadic-macros 
> -Wvolatile-register-var -Wwrite-strings -Wmissing-declarations 
> -Wmissing-parameter-type -Wnested-externs -Wstrict-prototypes -Wpointer-sign"
>  HOST_CFLAGS="$HOST_CFLAGS $WARN_FLAGS"
>  TARGET_CFLAGS="$TARGET_CFLAGS $WARN_FLAGS -g -Wredundant-decls 
> -Wmissing-prototypes"
>  TARGET_CCASFLAGS="$TARGET_CCASFLAGS -g"
[snip]


OK I checked out the latest bzr tree, and applied this patch.

I now get:
../../grub-core/gnulib/argp.h:610:1: warning: no previous declaration for 
'argp_usage' [-Wmissing-declarations]
../../grub-core/gnulib/argp.h:616:1: warning: no previous declaration for 
'_option_is_short' [-Wmissing-declarations]
../../grub-core/gnulib/argp.h:628:1: warning: no previous declaration for 
'_option_is_end' [-Wmissing-declarations]

instead of the missing prototypes.

Other than that we are down to:
../../grub-core/disk/ldm.c:834: warning: 'res_lv' may be used uninitialized in 
this function
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
../../grub-core/lib/minilzo/minilzo.c:4187: warning: logical '&&' with non-zero 
constant will always evaluate as true
../../grub-core/lib/minilzo/minilzo.c:4526: warning: logical '&&' with non-zero 
constant will always evaluate as true
grub_script.tab.c:2134: warning: cannot optimize loop, the loop counter may 
overflow
../../grub-core/lib/libgcrypt-grub/cipher/serpent.c:591: warning: comparison 
between signed and unsigned integer expressions
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:173: warning: comparison 
between signed and unsigned integer expressions
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:324: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:324: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:347: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:371: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:515: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:539: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:562: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:582: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
../../util/grub-mkfont.c:720: warning: cannot optimize possibly infinite loops
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
../../../grub-core/gnulib/regexec.c:2802: warning: cannot optimize possibly 
infinite loops
../../../grub-core/gnulib/regexec.c:2443: warning: cannot optimize possibly 
infinite loops
../../../grub-core/gnulib/regcomp.c:2588: warning: cannot optimize possibly 
infinite loops
../../../grub-core/gnulib/regcomp.c:2554: warning: cannot optimize possibly 
infinite loops
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
../../../grub-core/normal/charset.c:737: warning: cannot optimize possibly 
infinite loops
grub_script.tab.c:2134: warning: cannot optimize loop, the loop counter may 
overflow
../../../grub-core/net/net.c:621: warning: cannot optimize possibly infinite 
loops
../../../grub-core/commands/legacycfg.c:567: warning: cannot optimize loop, the 
loop counter may overflow
../../../grub-core/lib/minilzo/minilzo.c:4187: warning: logical '&&' with 
non-zero constant will always evaluate as true
../../../grub-core/lib/minilzo/minilzo.c:4526: warning: logical '&&' with 
non-zero constant will always evaluate as true
../../../grub-core/lib/libgcrypt-grub/cipher/serpent.c:591: warning: comparison 
between signed and unsigned integer expressions
../../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:173: warning: 
comparison between signed and unsigned integer expressions
grub.po: warning: Charset "CHARSET" is not a portable encoding name.
../../grub-core/disk/ldm.c:834: warning: 'res_lv' may be used uninitialized in 
this function
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
../../grub-core/lib/minilzo/minilzo.c:4187: warning: logical '&&' with non-zero 
constant will always evaluate as true
../../grub-core/lib/minilzo/minilzo.c:4526: warning: logical '&&' with non-zero 
constant will always evaluate as true
grub_script.tab.c:2134: warning: cannot optimize loop, the loop counter may 
overflow
../../grub-core/lib/libgcrypt-grub/cipher/serpent.c:591: warning: comparison 
between signed and unsigned integer expressions
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:173: warning: comparison 
between signed and unsigned integer expressions
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:324: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:324: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:347: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:371: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:515: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:539: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:562: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:582: warning: 
dereferencing type-punned pointer will break strict-aliasing rules
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
../../util/grub-mkfont.c:720: warning: cannot optimize possibly infinite loops
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
../../../grub-core/gnulib/regexec.c:2802: warning: cannot optimize possibly 
infinite loops
../../../grub-core/gnulib/regexec.c:2443: warning: cannot optimize possibly 
infinite loops
../../../grub-core/gnulib/regcomp.c:2588: warning: cannot optimize possibly 
infinite loops
../../../grub-core/gnulib/regcomp.c:2554: warning: cannot optimize possibly 
infinite loops
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations"
../../../grub-core/normal/charset.c:737: warning: cannot optimize possibly 
infinite loops
grub_script.tab.c:2134: warning: cannot optimize loop, the loop counter may 
overflow
../../../grub-core/net/net.c:621: warning: cannot optimize possibly infinite 
loops
../../../grub-core/lib/minilzo/minilzo.c:4187: warning: logical '&&' with 
non-zero constant will always evaluate as true
../../../grub-core/lib/minilzo/minilzo.c:4526: warning: logical '&&' with 
non-zero constant will always evaluate as true
../../../grub-core/lib/libgcrypt-grub/cipher/serpent.c:591: warning: comparison 
between signed and unsigned integer expressions
../../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:173: warning: 
comparison between signed and unsigned integer expressions

Apparently gcc 4.4 doesn't like -Wno-unsafe-loop-optimisations.  Neither does 
gcc 4.6:
../../grub-core/disk/ldm.c:850:6: warning: 'res_lv' may be used uninitialized 
in this function [-Wuninitialized]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
../../grub-core/lib/libgcrypt-grub/cipher/serpent.c:591:17: warning: comparison 
between signed and unsigned integer expressions [-Wsign-compare]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:173:21: warning: 
comparison between signed and unsigned integer expressions [-Wsign-compare]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:324:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:324:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:347:7: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:371:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:515:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:539:7: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:562:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:582:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
../../util/grub-mkfont.c:720:7: warning: cannot optimize possibly infinite 
loops [-Wunsafe-loop-optimizations]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
../../../grub-core/normal/charset.c:737:6: warning: cannot optimize possibly 
infinite loops [-Wunsafe-loop-optimizations]
../../../grub-core/commands/legacycfg.c:567:3: warning: cannot optimize loop, 
the loop counter may overflow [-Wunsafe-loop-optimizations]
../../../grub-core/lib/libgcrypt-grub/cipher/serpent.c:591:17: warning: 
comparison between signed and unsigned integer expressions [-Wsign-compare]
../../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:173:21: warning: 
comparison between signed and unsigned integer expressions [-Wsign-compare]
grub.po: warning: Charset "CHARSET" is not a portable encoding name.
../../grub-core/disk/ldm.c:850:6: warning: 'res_lv' may be used uninitialized 
in this function [-Wuninitialized]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
../../grub-core/lib/libgcrypt-grub/cipher/serpent.c:591:17: warning: comparison 
between signed and unsigned integer expressions [-Wsign-compare]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:173:21: warning: 
comparison between signed and unsigned integer expressions [-Wsign-compare]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:324:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:324:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:347:7: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:371:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:515:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:539:7: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:562:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:582:3: warning: 
dereferencing type-punned pointer will break strict-aliasing rules 
[-Wstrict-aliasing]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
../../util/grub-mkfont.c:720:7: warning: cannot optimize possibly infinite 
loops [-Wunsafe-loop-optimizations]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
cc1: warning: unrecognized command line option "-Wno-unsafe-loop-optimisations" 
[enabled by default]
../../../grub-core/normal/charset.c:737:6: warning: cannot optimize possibly 
infinite loops [-Wunsafe-loop-optimizations]
../../../grub-core/lib/libgcrypt-grub/cipher/serpent.c:591:17: warning: 
comparison between signed and unsigned integer expressions [-Wsign-compare]
../../../grub-core/lib/libgcrypt-grub/cipher/rijndael.c:173:21: warning: 
comparison between signed and unsigned integer expressions [-Wsign-compare]

I don't think -Wno-unsafe-loop-optimisations is valid.  One has to remove
-Wunsafe-loop-optimisations instead, which is currently in WARN_FLAGS.

-- 
Len Sorensen