Only try to parse git hash if .git is present

Closes 2451

build.bat

@@ -48,8 +48,11 @@ set odin_version_raw="dev-%curr_year%-%curr_month%"
 set compiler_flags= -nologo -Oi -TP -fp:precise -Gm- -MP -FC -EHsc- -GR- -GF
 set compiler_defines= -DODIN_VERSION_RAW=\"%odin_version_raw%\"
 
+if not exist .git\ goto skip_git_hash
 for /f %%i in ('git rev-parse --short HEAD') do set GIT_SHA=%%i
 if %ERRORLEVEL% equ 0 set compiler_defines=%compiler_defines% -DGIT_SHA=\"%GIT_SHA%\"
+:skip_git_hash
+
 if %nightly% equ 1 set compiler_defines=%compiler_defines% -DNIGHTLY
 
 if %release_mode% EQU 0 ( rem Debug

build_odin.sh

@@ -6,13 +6,18 @@ set -eu
 : ${CXXFLAGS=}
 : ${LDFLAGS=}
 : ${ODIN_VERSION=dev-$(date +"%Y-%m")}
+: ${GIT_SHA=}
 
 CPPFLAGS="$CPPFLAGS -DODIN_VERSION_RAW=\"$ODIN_VERSION\""
 CXXFLAGS="$CXXFLAGS -std=c++14"
 LDFLAGS="$LDFLAGS -pthread -lm -lstdc++"
 
-GIT_SHA=$(git rev-parse --short HEAD || :)
-if [ "$GIT_SHA" ]; then CPPFLAGS="$CPPFLAGS -DGIT_SHA=\"$GIT_SHA\""; fi
+if [ -d ".git" ]; then
+	GIT_SHA=$(git rev-parse --short HEAD || :)
+	if [ "$GIT_SHA" ]; then
+		CPPFLAGS="$CPPFLAGS -DGIT_SHA=\"$GIT_SHA\""
+	fi
+fi
 
 DISABLED_WARNINGS="-Wno-switch -Wno-macro-redefined -Wno-unused-value"
 OS=$(uname)