[clang] clang/win: Add a flag to disable default-linking of compiler-rt libraries (PR #89642)
Nico Weber via cfe-commits
cfe-commits at lists.llvm.org
Tue Apr 23 05:12:40 PDT 2024
https://github.com/nico updated https://github.com/llvm/llvm-project/pull/89642
>From 39bd2d2ece1f55c3c77e1f376913846fb604be27 Mon Sep 17 00:00:00 2001
From: Nico Weber <thakis at chromium.org>
Date: Mon, 22 Apr 2024 14:05:04 -0400
Subject: [PATCH] clang/win: Add a flag to disable default-linking of
compiler-rt libraries
For ASan, users already manually have to pass in the path to the lib,
and for other libraries they have to pass in the path to the libpath.
With LLVM's unreliable name of the lib (due to
LLVM_ENABLE_PER_TARGET_RUNTIME_DIR confusion and whatnot), it's useful
to be able to opt in to just explicitly passing the paths to the libs
everywhere.
Follow-up of sorts to https://reviews.llvm.org/D65543, and to #87866.
---
clang/docs/UsersManual.rst | 3 +++
clang/include/clang/Driver/Options.td | 8 ++++++++
clang/lib/Driver/SanitizerArgs.cpp | 8 ++++++--
clang/lib/Driver/ToolChains/Clang.cpp | 8 ++++++--
clang/test/Driver/cl-options.c | 4 ++++
clang/test/Driver/sanitizer-ld.c | 14 ++++++++++++++
6 files changed, 41 insertions(+), 4 deletions(-)
diff --git a/clang/docs/UsersManual.rst b/clang/docs/UsersManual.rst
index c464bc3a69adc5..8df40566fcba3d 100644
--- a/clang/docs/UsersManual.rst
+++ b/clang/docs/UsersManual.rst
@@ -4921,6 +4921,9 @@ directory. Using the example installation above, this would mean passing
If the user links the program with the ``clang`` or ``clang-cl`` drivers, the
driver will pass this flag for them.
+The auto-linking can be disabled with -fno-rtlib-defaultlib. If that flag is
+used, pass the complete flag to required libraries as described for ASan below.
+
If the linker cannot find the appropriate library, it will emit an error like
this::
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 9f86808145d9ab..902eb450a7e042 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -5502,6 +5502,14 @@ def fno_rtlib_add_rpath: Flag<["-"], "fno-rtlib-add-rpath">,
Visibility<[ClangOption, FlangOption]>,
HelpText<"Do not add -rpath with architecture-specific resource directory to the linker flags. "
"When --hip-link is specified, do not add -rpath with HIP runtime library directory to the linker flags">;
+def frtlib_defaultlib : Flag<["-"], "frtlib-defaultlib">,
+ Visibility<[ClangOption, CLOption]>,
+ Group<f_Group>,
+ HelpText<"On Windows, emit /defaultlib: directives to link compiler-rt libraries (default)">;
+def fno_rtlib_defaultlib : Flag<["-"], "fno-rtlib-defaultlib">,
+ Visibility<[ClangOption, CLOption]>,
+ Group<f_Group>,
+ HelpText<"On Windows, do not emit /defaultlib: directives to link compiler-rt libraries">;
def offload_add_rpath: Flag<["--"], "offload-add-rpath">,
Flags<[NoArgumentUnused]>,
Alias<frtlib_add_rpath>;
diff --git a/clang/lib/Driver/SanitizerArgs.cpp b/clang/lib/Driver/SanitizerArgs.cpp
index 8bfe9f02a091d1..6a4f2548c0bffa 100644
--- a/clang/lib/Driver/SanitizerArgs.cpp
+++ b/clang/lib/Driver/SanitizerArgs.cpp
@@ -1192,7 +1192,9 @@ void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
BinaryMetadataIgnorelistFiles);
}
- if (TC.getTriple().isOSWindows() && needsUbsanRt()) {
+ if (TC.getTriple().isOSWindows() && needsUbsanRt() &&
+ Args.hasFlag(options::OPT_frtlib_defaultlib,
+ options::OPT_fno_rtlib_defaultlib, true)) {
// Instruct the code generator to embed linker directives in the object file
// that cause the required runtime libraries to be linked.
CmdArgs.push_back(
@@ -1203,7 +1205,9 @@ void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
"--dependent-lib=" +
TC.getCompilerRTBasename(Args, "ubsan_standalone_cxx")));
}
- if (TC.getTriple().isOSWindows() && needsStatsRt()) {
+ if (TC.getTriple().isOSWindows() && needsStatsRt() &&
+ Args.hasFlag(options::OPT_frtlib_defaultlib,
+ options::OPT_fno_rtlib_defaultlib, true)) {
CmdArgs.push_back(Args.MakeArgString(
"--dependent-lib=" + TC.getCompilerRTBasename(Args, "stats_client")));
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index f8a81ee8ab56bc..3d31ac3cd0e34c 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -637,7 +637,9 @@ static void addPGOAndCoverageFlags(const ToolChain &TC, Compilation &C,
ProfileGenerateArg->getValue()));
// The default is to use Clang Instrumentation.
CmdArgs.push_back("-fprofile-instrument=clang");
- if (TC.getTriple().isWindowsMSVCEnvironment()) {
+ if (TC.getTriple().isWindowsMSVCEnvironment() &&
+ Args.hasFlag(options::OPT_frtlib_defaultlib,
+ options::OPT_fno_rtlib_defaultlib, true)) {
// Add dependent lib for clang_rt.profile
CmdArgs.push_back(Args.MakeArgString(
"--dependent-lib=" + TC.getCompilerRTBasename(Args, "profile")));
@@ -656,7 +658,9 @@ static void addPGOAndCoverageFlags(const ToolChain &TC, Compilation &C,
CmdArgs.push_back("-fprofile-instrument=csllvm");
}
if (PGOGenArg) {
- if (TC.getTriple().isWindowsMSVCEnvironment()) {
+ if (TC.getTriple().isWindowsMSVCEnvironment() &&
+ Args.hasFlag(options::OPT_frtlib_defaultlib,
+ options::OPT_fno_rtlib_defaultlib, true)) {
// Add dependent lib for clang_rt.profile
CmdArgs.push_back(Args.MakeArgString(
"--dependent-lib=" + TC.getCompilerRTBasename(Args, "profile")));
diff --git a/clang/test/Driver/cl-options.c b/clang/test/Driver/cl-options.c
index 7731300ae9f525..75f49deca0653d 100644
--- a/clang/test/Driver/cl-options.c
+++ b/clang/test/Driver/cl-options.c
@@ -70,12 +70,16 @@
// fsanitize_address: -fsanitize=address
// RUN: %clang_cl -### /FA -fprofile-instr-generate -- %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-INSTR-GENERATE %s
+// RUN: %clang_cl -### /FA -fprofile-instr-generate -fno-rtlib-defaultlib -frtlib-defaultlib -- %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-INSTR-GENERATE %s
// RUN: %clang_cl -### /FA -fprofile-instr-generate=/tmp/somefile.profraw -- %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-INSTR-GENERATE-FILE %s
// RUN: %clang_cl -### /FAcsu -fprofile-instr-generate -- %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-INSTR-GENERATE %s
// RUN: %clang_cl -### /FAcsu -fprofile-instr-generate=/tmp/somefile.profraw -- %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-INSTR-GENERATE-FILE %s
// CHECK-PROFILE-INSTR-GENERATE: "-fprofile-instrument=clang" "--dependent-lib=clang_rt.profile{{[^"]*}}.lib"
// CHECK-PROFILE-INSTR-GENERATE-FILE: "-fprofile-instrument-path=/tmp/somefile.profraw"
+// RUN: %clang_cl -### /FA -fprofile-instr-generate -fno-rtlib-defaultlib -- %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-INSTR-GENERATE-NODEF %s
+// CHECK-PROFILE-INSTR-GENERATE-NODEF-NOT: "--dependent-lib=clang_rt.profile{{[^"]*}}.lib"
+
// RUN: %clang_cl -### /FA -fprofile-generate -- %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-GENERATE %s
// RUN: %clang_cl -### /FAcsu -fprofile-generate -- %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-GENERATE %s
// CHECK-PROFILE-GENERATE: "-fprofile-instrument=llvm" "--dependent-lib=clang_rt.profile{{[^"]*}}.lib"
diff --git a/clang/test/Driver/sanitizer-ld.c b/clang/test/Driver/sanitizer-ld.c
index f5657e47626e1d..7289d09697b4d0 100644
--- a/clang/test/Driver/sanitizer-ld.c
+++ b/clang/test/Driver/sanitizer-ld.c
@@ -802,10 +802,24 @@
// RUN: --target=i686-pc-windows \
// RUN: --sysroot=%S/Inputs/basic_linux_tree \
// RUN: | FileCheck --check-prefix=CHECK-CFI-STATS-WIN32 %s
+// RUN: not %clang -fsanitize=cfi -fsanitize-stats -### %s 2>&1 \
+// RUN: --target=i686-pc-windows \
+// RUN: -fno-rtlib-defaultlib \
+// RUN: -frtlib-defaultlib \
+// RUN: --sysroot=%S/Inputs/basic_linux_tree \
+// RUN: | FileCheck --check-prefix=CHECK-CFI-STATS-WIN32 %s
// CHECK-CFI-STATS-WIN32: "--dependent-lib=clang_rt.stats_client{{(-i386)?}}.lib"
// CHECK-CFI-STATS-WIN32: "--dependent-lib=clang_rt.stats{{(-i386)?}}.lib"
// CHECK-CFI-STATS-WIN32: "--linker-option=/include:___sanitizer_stats_register"
+// RUN: not %clang -fsanitize=cfi -fsanitize-stats -### %s 2>&1 \
+// RUN: --target=i686-pc-windows \
+// RUN: -fno-rtlib-defaultlib \
+// RUN: --sysroot=%S/Inputs/basic_linux_tree \
+// RUN: | FileCheck --check-prefix=CHECK-CFI-STATS-WIN32-NODEF %s
+// CHECK-CFI-STATS-WIN32-NODEF-NOT: "--dependent-lib=clang_rt.stats_client{{(-i386)?}}.lib"
+// CHECK-CFI-STATS-WIN32-NODEF-NOT: "--dependent-lib=clang_rt.stats{{(-i386)?}}.lib"
+
// RUN: %clang -### %s 2>&1 \
// RUN: --target=arm-linux-androideabi -fuse-ld=ld -fsanitize=safe-stack \
// RUN: --sysroot=%S/Inputs/basic_android_tree \
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