attack the biggest stack users:

-mkfs_minix_main [busybox_unstripped]:                  4288
-mkfs_minix_main [busybox_unstripped]:                  4276
-grave [busybox_unstripped]:                            4260
(bzip2 users too - not listed)

price we pay in code size increase:
mainSort                                            2458    2515     +57
grave                                               1005    1058     +53
sendMTFValues                                       2177    2195     +18
BZ2_blockSort                                        122     125      +3
mkfs_minix_main                                     3070    3022     -48
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 4/1 up/down: 131/-48)            Total: 83 bytes

1 files changed, 21 insertions, 3 deletions

diff --git a/util-linux/mkfs_minix.c b/util-linux/mkfs_minix.c
index de9dde32b..35c0ccf5c 100644
--- a/util-linux/mkfs_minix.c
+++ b/util-linux/mkfs_minix.c
@@ -109,16 +109,22 @@ struct globals {
         unsigned long req_nr_inodes;
         unsigned currently_testing;
 
-
         char root_block[BLOCK_SIZE];
         char super_block_buffer[BLOCK_SIZE];
         char boot_block_buffer[512];
         unsigned short good_blocks_table[MAX_GOOD_BLOCKS];
         /* check_blocks(): buffer[] was the biggest static in entire bbox */
         char check_blocks_buffer[BLOCK_SIZE * TEST_BUFFER_BLOCKS];
-};
 
+        unsigned short ind_block1[BLOCK_SIZE >> 1];
+        unsigned short dind_block1[BLOCK_SIZE >> 1];
+        unsigned long ind_block2[BLOCK_SIZE >> 2];
+        unsigned long dind_block2[BLOCK_SIZE >> 2];
+};
 #define G (*ptr_to_globals)
+#define INIT_G() do { \
+        PTR_TO_GLOBALS = xzalloc(sizeof(G)); \
+} while (0)
 
 static ALWAYS_INLINE unsigned div_roundup(unsigned size, unsigned n)
 {
@@ -306,8 +312,12 @@ static void make_bad_inode(void)
         struct minix1_inode *inode = &INODE_BUF1[MINIX_BAD_INO];
         int i, j, zone;
         int ind = 0, dind = 0;
+        /* moved to globals to reduce stack usage
         unsigned short ind_block[BLOCK_SIZE >> 1];
         unsigned short dind_block[BLOCK_SIZE >> 1];
+        */
+#define ind_block (G.ind_block1)
+#define dind_block (G.dind_block1)
 
 #define NEXT_BAD (zone = next(zone))
 
@@ -351,6 +361,8 @@ static void make_bad_inode(void)
                 write_block(ind, (char *) ind_block);
         if (dind)
                 write_block(dind, (char *) dind_block);
+#undef ind_block
+#undef dind_block
 }
 
 #if ENABLE_FEATURE_MINIX2
@@ -359,8 +371,12 @@ static void make_bad_inode2(void)
         struct minix2_inode *inode = &INODE_BUF2[MINIX_BAD_INO];
         int i, j, zone;
         int ind = 0, dind = 0;
+        /* moved to globals to reduce stack usage
         unsigned long ind_block[BLOCK_SIZE >> 2];
         unsigned long dind_block[BLOCK_SIZE >> 2];
+        */
+#define ind_block (G.ind_block2)
+#define dind_block (G.dind_block2)
 
         if (!G.badblocks)
                 return;
@@ -401,6 +417,8 @@ static void make_bad_inode2(void)
                 write_block(ind, (char *) ind_block);
         if (dind)
                 write_block(dind, (char *) dind_block);
+#undef ind_block
+#undef dind_block
 }
 #else
 void make_bad_inode2(void);
@@ -613,7 +631,7 @@ int mkfs_minix_main(int argc, char **argv)
         char *str_i, *str_n;
         char *listfile = NULL;
 
-        PTR_TO_GLOBALS = xzalloc(sizeof(G));
+        INIT_G();
 /* default (changed to 30, per Linus's suggestion, Sun Nov 21 08:05:07 1993) */
         G.namelen = 30;
         G.dirsize = 32;