diff --git a/src/libs/botan/botan.pro b/src/libs/botan/botan.pro
index 04feb8d3292..48b3b2ea359 100644
--- a/src/libs/botan/botan.pro
+++ b/src/libs/botan/botan.pro
@@ -30,7 +30,7 @@ mingw {
 BOTAN_CXX_FLAGS =
 msvc: BOTAN_CXX_FLAGS += /wd4127 /wd4244 /wd4250 /wd4267 /wd4334 /wd4702 /wd4996
 else: BOTAN_CXX_FLAGS += -Wno-unused-parameter
-macos: BOTAN_CXX_FLAGS += -mmacosx-version-min=$$QMAKE_MACOSX_DEPLOYMENT_TARGET
+macos: BOTAN_CXX_FLAGS += -mmacosx-version-min=$$QMAKE_MACOSX_DEPLOYMENT_TARGET -isysroot $$shell_quote($$QMAKE_MAC_SDK.macosx.Path)
 unix: BOTAN_CXX_FLAGS += -fPIC
 !isEmpty(BOTAN_CXX_FLAGS): OTHER_FLAGS += --cxxflags=$$shell_quote($$BOTAN_CXX_FLAGS)
 win32: OTHER_FLAGS += --link-method=hardlink
diff --git a/src/libs/botan/botan.qbs b/src/libs/botan/botan.qbs
index 04acfad0484..3872e900adb 100644
--- a/src/libs/botan/botan.qbs
+++ b/src/libs/botan/botan.qbs
@@ -6,6 +6,7 @@ Product {
     type: ["staticlibrary", "hpp"]
     Depends { name: "cpp" }
     Depends { name: "qtc" }
+    Depends { name: "xcode"; condition: qbs.toolchain.contains("xcode") }
     files: "update-botan.sh"
     Group {
         name: "Botan sources"
@@ -47,8 +48,11 @@ Product {
             }
             else if (product.qbs.toolchain.contains("gcc"))
                 cxxFlags.push("-Wno-unused-parameter");
-            if (product.qbs.targetOS.contains("macos"))
+            if (product.qbs.targetOS.contains("macos")) {
                 cxxFlags.push("-mmacosx-version-min=" + project.minimumMacosVersion);
+                if (product.qbs.toolchain.contains("xcode"))
+                    cxxFlags.push("-isysroot", product.xcode.sdkPath);
+            }
             if (product.qbs.targetOS.contains("unix"))
                 cxxFlags.push("-fPIC");
             if (cxxFlags.length > 0)