diff options
| author | Denys Vlasenko <vda.linux@googlemail.com> | 2015-10-07 22:42:45 +0200 |
|---|---|---|
| committer | Denys Vlasenko <vda.linux@googlemail.com> | 2015-10-07 22:42:45 +0200 |
| commit | d60752f8c9be5689a249ad518deb38061d4bc45e (patch) | |
| tree | 06df5c7e22be59561cbbcd22eb63ff95344fe321 /Makefile.flags | |
| parent | 8c0708a329618b20089eb9cedbe06522dd25d9be (diff) | |
build system: -fno-builtin-printf
Benefits are: drops reference to out-of-line putchar(), fixes a few cases
of failed string merge.
function old new delta
i2cdump_main 1488 1502 +14
sha256_process_block64 423 433 +10
sendmail_main 1183 1185 +2
list_table 1114 1116 +2
i2cdetect_main 1235 1237 +2
fdisk_main 2852 2854 +2
builtin_type 119 121 +2
unicode_conv_to_printable2 325 324 -1
scan_recursive 380 378 -2
mkfs_minix_main 2687 2684 -3
buffer_fill_and_print 178 169 -9
putchar 152 - -152
------------------------------------------------------------------------------
(add/remove: 0/2 grow/shrink: 7/4 up/down: 34/-167) Total: -133 bytes
text data bss dec hex filename
937788 932 17676 956396 e97ec busybox_old
937564 932 17676 956172 e970c busybox_unstripped
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'Makefile.flags')
| -rw-r--r-- | Makefile.flags | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/Makefile.flags b/Makefile.flags index 2bc83d1d9..b6cd32e42 100644 --- a/Makefile.flags +++ b/Makefile.flags @@ -56,6 +56,9 @@ CFLAGS += $(call cc-option,-falign-functions=1 -falign-jumps=1 -falign-labels=1 # Defeat .eh_frame bloat (gcc 4.6.3 x86-32 defconfig: 20% smaller busybox binary): CFLAGS += $(call cc-option,-fno-unwind-tables,) CFLAGS += $(call cc-option,-fno-asynchronous-unwind-tables,) +# No automatic printf->puts,putchar conversions +# (try disabling this and comparing assembly, it's instructive) +CFLAGS += $(call cc-option,-fno-builtin-printf,) # FIXME: These warnings are at least partially to be concerned about and should # be fixed.. |