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[PATCH 1/2] mingw: do not let ld strip relocations




From: =?UTF-8?q?=C4=B0smail=20D=C3=B6nmez?= <ismail@xxxxxxxx>

This is the first step for enabling ASLR (Address Space Layout
Randomization) support. We want to enable ASLR for better protection
against exploiting security holes in Git: it makes it harder to attack
software by making code addresses unpredictable.

The problem fixed by this commit is that `ld.exe` seems to be stripping
relocations which in turn will break ASLR support. We just make sure
it's not stripping the main executable entry.

Signed-off-by: İsmail Dönmez <ismail@xxxxxxxx>
Signed-off-by: Johannes Schindelin <johannes.schindelin@xxxxxx>
---
 config.mak.uname | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/config.mak.uname b/config.mak.uname
index b37fa8424c..e7c7d14e5f 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -573,10 +573,12 @@ else
 		ifeq (MINGW32,$(MSYSTEM))
 			prefix = /mingw32
 			HOST_CPU = i686
+			BASIC_LDFLAGS += -Wl,--pic-executable,-e,_mainCRTStartup
 		endif
 		ifeq (MINGW64,$(MSYSTEM))
 			prefix = /mingw64
 			HOST_CPU = x86_64
+			BASIC_LDFLAGS += -Wl,--pic-executable,-e,mainCRTStartup
 		else
 			COMPAT_CFLAGS += -D_USE_32BIT_TIME_T
 			BASIC_LDFLAGS += -Wl,--large-address-aware
-- 
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