[PATCH 1/2] Makefile: not use mismatched curl_config to check version

[Jiang Xin <worldhello.net@gmail.com>]

From: Jiang Xin <zhiyou.jx@alibaba-inc.com>

We may install different versions of curl, E.g.:

 * A system default curl, which version is below 7.34.0, is installed
   in "/usr", and the "curl_config" program is located in "/usr/bin/".

 * A higher version of curl is installed in "/opt/git/embedded/", and
   the "curl_config" program is located in "/opt/git/embedded/bin/".

If we add the path "/opt/git/embedded/bin" in search PATH, and install
git using command "make && sudo make install", the source code may be
compiled twice.

This is because when we run "make" using normal user account, make will
call "/opt/git/embedded/bin/curl_config" to check curl version, and will
set variable USE_CURL_FOR_IMAP_SEND. But when we call "make install"
using root user's account, we call the system default version of
curl_config to check curl version, and will lead to a different
"GIT-CFLAGS" file, and will recompile all source code again.

Append "$(CURLDIR)/bin" before the "CURL_CONFIG" variable to use the
specific "curl_config" program we want to check curl version, we will
get the correct "CURL_CFLAGS" and "CURL_LDFLAGS" variables, and we can
also have a stable "GIT-CFLAGS" file to prevent recompile when running
"sudo make install".

Signed-off-by: Jiang Xin <zhiyou.jx@alibaba-inc.com>
---
 Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Makefile b/Makefile
index 45bd6ac9c3..f4eaf22523 100644
--- a/Makefile
+++ b/Makefile
@@ -1597,6 +1597,7 @@ else
 		# Try "-Wl,-rpath=$(CURLDIR)/$(lib)" in such a case.
 		CURL_CFLAGS = -I$(CURLDIR)/include
 		CURL_LIBCURL = -L$(CURLDIR)/$(lib) $(CC_LD_DYNPATH)$(CURLDIR)/$(lib)
+		CURL_CONFIG := $(CURLDIR)/bin/$(CURL_CONFIG)
 	else
 		CURL_CFLAGS =
 		CURL_LIBCURL =
-- 
2.38.2.109.g8b8c02ffae.agit.6.7.7.dev