[driver][darwin] Don't use -platform_version flag by default (PR44813)

The code in llvmorg-10-init-12188-g25ce33a6e4f is a breaking change for
users of older linkers who don't pass a version parameter, which
prevents a drop-in clang upgrade. Old tools can't know about what future
tools will do, so as a general principle the burden should be new tools
to be compatible by default. Also, for comparison, none of the other
tests of Version within AddLinkArgs add any new behaviors unless the
version is explicitly specified. Therefore, this patch changes the
-platform_version behavior from opt-out to opt-in.

Patch by David Major!

Differential revision: https://reviews.llvm.org/D74784

diff --git a/clang/lib/Driver/ToolChains/Darwin.cpp b/clang/lib/Driver/ToolChains/Darwin.cpp
index b32fad7..ab3a68b 100644 (file)
--- a/clang/lib/Driver/ToolChains/Darwin.cpp
+++ b/clang/lib/Driver/ToolChains/Darwin.cpp
@@ -335,7 +335,7 @@ void darwin::Linker::AddLinkArgs(Compilation &C, const ArgList &Args,
   Args.AddAllArgs(CmdArgs, options::OPT_init);
 
   // Add the deployment target.
-  if (!Version[0] || Version[0] >= 520)
+  if (Version[0] >= 520)
     MachOTC.addPlatformVersionArgs(Args, CmdArgs);
   else
     MachOTC.addMinVersionArgs(Args, CmdArgs);

diff --git a/clang/test/Driver/darwin-ld-platform-version-ios.c b/clang/test/Driver/darwin-ld-platform-version-ios.c
index 2255d3f..0569803 100644 (file)
--- a/clang/test/Driver/darwin-ld-platform-version-ios.c
+++ b/clang/test/Driver/darwin-ld-platform-version-ios.c
@@ -1,9 +1,14 @@
 // RUN: touch %t.o
 
+// RUN: %clang -target arm64-apple-ios12.3 -isysroot %S/Inputs/iPhoneOS13.0.sdk -mlinker-version=0 -### %t.o 2>&1 \
+// RUN:   | FileCheck --check-prefix=LINKER-OLD %s
+// RUN: %clang -target arm64-apple-ios12.3 -isysroot %S/Inputs/iPhoneOS13.0.sdk -mlinker-version=400 -### %t.o 2>&1 \
+// RUN:   | FileCheck --check-prefix=LINKER-OLD %s
 // RUN: %clang -target arm64-apple-ios12.3 -isysroot %S/Inputs/iPhoneOS13.0.sdk -mlinker-version=520 -### %t.o 2>&1 \
-// RUN:   | FileCheck %s
+// RUN:   | FileCheck --check-prefix=LINKER-NEW  %s
 // RUN: %clang -target x86_64-apple-ios13-simulator -isysroot %S/Inputs/iPhoneOS13.0.sdk -mlinker-version=520 -### %t.o 2>&1 \
 // RUN:   | FileCheck --check-prefix=SIMUL %s
 
-// CHECK: "-platform_version" "ios" "12.3.0" "13.0"
+// LINKER-OLD: "-iphoneos_version_min" "12.3.0"
+// LINKER-NEW: "-platform_version" "ios" "12.3.0" "13.0"
 // SIMUL: "-platform_version" "ios-simulator" "13.0.0" "13.0"

diff --git a/clang/test/Driver/darwin-ld-platform-version-macos.c b/clang/test/Driver/darwin-ld-platform-version-macos.c
index 1b849a6..c1b940a 100644 (file)
--- a/clang/test/Driver/darwin-ld-platform-version-macos.c
+++ b/clang/test/Driver/darwin-ld-platform-version-macos.c
@@ -1,11 +1,14 @@
 // RUN: touch %t.o
 
 // RUN: %clang -target x86_64-apple-macos10.13 -isysroot %S/Inputs/MacOSX10.14.sdk -mlinker-version=0 -### %t.o 2>&1 \
-// RUN:   | FileCheck %s
+// RUN:   | FileCheck --check-prefix=LINKER-OLD %s
+// RUN: %clang -target x86_64-apple-macos10.13 -isysroot %S/Inputs/MacOSX10.14.sdk -mlinker-version=400 -### %t.o 2>&1 \
+// RUN:   | FileCheck --check-prefix=LINKER-OLD %s
 // RUN: env SDKROOT=%S/Inputs/MacOSX10.14.sdk %clang -target x86_64-apple-macos10.13.0.1 -mlinker-version=520 -### %t.o 2>&1 \
-// RUN:   | FileCheck %s
+// RUN:   | FileCheck --check-prefix=LINKER-NEW %s
 
-// CHECK: "-platform_version" "macos" "10.13.0" "10.14"
+// LINKER-OLD: "-macosx_version_min" "10.13.0"
+// LINKER-NEW: "-platform_version" "macos" "10.13.0" "10.14"
 
 // RUN: %clang -target x86_64-apple-macos10.13  -mlinker-version=520 -### %t.o 2>&1 \
 // RUN:   | FileCheck --check-prefix=NOSDK %s

diff --git a/clang/test/Driver/darwin-ld-platform-version-tvos.c b/clang/test/Driver/darwin-ld-platform-version-tvos.c
index 1ef6a0b..39a2020 100644 (file)
--- a/clang/test/Driver/darwin-ld-platform-version-tvos.c
+++ b/clang/test/Driver/darwin-ld-platform-version-tvos.c
@@ -1,9 +1,14 @@
 // RUN: touch %t.o
 
+// RUN: %clang -target arm64-apple-tvos12.3 -isysroot %S/Inputs/iPhoneOS13.0.sdk -mlinker-version=0 -### %t.o 2>&1 \
+// RUN:   | FileCheck --check-prefix=LINKER-OLD %s
+// RUN: %clang -target arm64-apple-tvos12.3 -isysroot %S/Inputs/iPhoneOS13.0.sdk -mlinker-version=400 -### %t.o 2>&1 \
+// RUN:   | FileCheck --check-prefix=LINKER-OLD %s
 // RUN: %clang -target arm64-apple-tvos12.3 -isysroot %S/Inputs/iPhoneOS13.0.sdk -mlinker-version=520 -### %t.o 2>&1 \
-// RUN:   | FileCheck %s
+// RUN:   | FileCheck --check-prefix=LINKER-NEW %s
 // RUN: %clang -target x86_64-apple-tvos13-simulator -isysroot %S/Inputs/iPhoneOS13.0.sdk -mlinker-version=520 -### %t.o 2>&1 \
 // RUN:   | FileCheck --check-prefix=SIMUL %s
 
-// CHECK: "-platform_version" "tvos" "12.3.0" "13.0"
+// LINKER-OLD: "-tvos_version_min" "12.3.0"
+// LINKER-NEW: "-platform_version" "tvos" "12.3.0" "13.0"
 // SIMUL: "-platform_version" "tvos-simulator" "13.0.0" "13.0"

diff --git a/clang/test/Driver/darwin-ld-platform-version-watchos.c b/clang/test/Driver/darwin-ld-platform-version-watchos.c
index 9663fc6..db565dd 100644 (file)
--- a/clang/test/Driver/darwin-ld-platform-version-watchos.c
+++ b/clang/test/Driver/darwin-ld-platform-version-watchos.c
@@ -1,9 +1,14 @@
 // RUN: touch %t.o
 
+// RUN: %clang -target arm64_32-apple-watchos5.2 -isysroot %S/Inputs/WatchOS6.0.sdk -mlinker-version=0 -### %t.o 2>&1 \
+// RUN:   | FileCheck --check-prefix=LINKER-OLD %s
+// RUN: %clang -target arm64_32-apple-watchos5.2 -isysroot %S/Inputs/WatchOS6.0.sdk -mlinker-version=400 -### %t.o 2>&1 \
+// RUN:   | FileCheck --check-prefix=LINKER-OLD %s
 // RUN: %clang -target arm64_32-apple-watchos5.2 -isysroot %S/Inputs/WatchOS6.0.sdk -mlinker-version=520 -### %t.o 2>&1 \
-// RUN:   | FileCheck %s
+// RUN:   | FileCheck --check-prefix=LINKER-NEW %s
 // RUN: %clang -target x86_64-apple-watchos6-simulator -isysroot %S/Inputs/WatchOS6.0.sdk -mlinker-version=520 -### %t.o 2>&1 \
 // RUN:   | FileCheck --check-prefix=SIMUL %s
 
-// CHECK: "-platform_version" "watchos" "5.2.0" "6.0.0"
+// LINKER-OLD: "-watchos_version_min" "5.2.0"
+// LINKER-NEW: "-platform_version" "watchos" "5.2.0" "6.0.0"
 // SIMUL: "-platform_version" "watchos-simulator" "6.0.0" "6.0.0"