Building git with /bin/sh⇔dash produces suboptimal GIT-CFLAGS file

["Дилян Палаузов" <dilyan.palauzov@aegee.org>]

Hello,

when /bin/sh is bash, target GIT-CFLAGS: FORCE in Makefile puts in the file GIT-CFLAGS the content

gcc:  -g -O2  -I. -DHAVE_SYSINFO -DGIT_HOST_CPU="\"x86_64\"" -DUSE_LIBPCRE2 -DHAVE_ALLOCA_H -I/usr/local/include -DUSE_CURL_FOR_IMAP_SEND -DSUPPORTS_SIMPLE_IPC -DSHA1_DC -DSHA1DC_NO_STANDARD_INCLUDES -DSHA1DC_INIT_SAFE_HASH_DEFAULT=0 -DSHA1DC_CUSTOM_INCLUDE_SHA1_C="\"git-compat-util.h\"" -DSHA1DC_CUSTOM_INCLUDE_UBC_CHECK_C="\"git-compat-util.h\"" -DSHA256_BLK  -DHAVE_PATHS_H -DHAVE_STRINGS_H -DHAVE_DEV_TTY -DHAVE_CLOCK_GETTIME -DHAVE_CLOCK_MONOTONIC -DHAVE_SYNC_FILE_RANGE -DHAVE_GETDELIM '-
DPROCFS_EXECUTABLE_PATH="/proc/self/exe"' -DFREAD_READS_DIRECTORIES -DSHELL_PATH='"/bin/sh"':

when /bin/sh is dash (b3e38ad), the same file GIT-CFLAGS contains

gcc:  -g -O2  -I. -DHAVE_SYSINFO -DGIT_HOST_CPU=""x86_64"" -DUSE_LIBPCRE2 -DHAVE_ALLOCA_H -I/usr/local/include -DUSE_CURL_FOR_IMAP_SEND -DSUPPORTS_SIMPLE_IPC -DSHA1_DC -DSHA1DC_NO_STANDARD_INCLUDES -DSHA1DC_INIT_SAFE_HASH_DEFAULT=0 -DSHA1DC_CUSTOM_INCLUDE_SHA1_C=""git-compat-util.h"" -DSHA1DC_CUSTOM_INCLUDE_UBC_CHECK_C=""git-compat-util.h"" -DSHA256_BLK  -DHAVE_PATHS_H -DHAVE_STRINGS_H -DHAVE_DEV_TTY -DHAVE_CLOCK_GETTIME -DHAVE_CLOCK_MONOTONIC -DHAVE_SYNC_FILE_RANGE -DHAVE_GETDELIM '-
DPROCFS_EXECUTABLE_PATH="/proc/self/exe"' -DFREAD_READS_DIRECTORIES -DSHELL_PATH='"/bin/sh"':

Note the differences in the -DGIT_HOST_CPU, -DSHA1DC_CUSTOM_INCLUDE_SHA1_C values.  Because of the differences, in Makefile:3150   if test x"$$FLAGS" != x"`cat GIT-CFLAGS 2>/dev/null`" ; then  always succeeds, prints “* new build flags” and every run of make starts rebuilding daemon.o.  So the empty build is not empty.

Greetings
  Дилян