From: Steve Lhomme <rob...@gmail.com>
Without any optimization flags, MSVC does no dead code elimination (DCE) at
all, even for the most trivial cases. DCE is a prerequisite for building ffmpeg
correctly, otherwise there are undefined references to functions for other
architectures and disabled components.
-Os -Og is the minimal optimization flags for MSVC that does include DCE. It
warns that -Og will be removed but it doesn't work without. -O1 includes these
flags and some other ones not necessary to link properly.
---
configure | 1 +
1 file changed, 1 insertion(+)
diff --git a/configure b/configure
index 9dfd006..1a8a05c 100755
--- a/configure
+++ b/configure
@@ -4087,6 +4087,7 @@ probe_cc(){
_DEPFLAGS='$(CPPFLAGS) $(CFLAGS) -showIncludes -Zs'
_cflags_speed="-O2"
_cflags_size="-O1"
+ _cflags_noopt="-Os -Og"
if $_cc -nologo- 2>&1 | grep -q Linker; then
_ld_o='-out:$@'
else
--
2.10.2
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