Include -mno-relax forwarding for GNU environment (ld)

According reviewer's suggestion.

Author: Andreu Carminati

clang/lib/Driver/ToolChains/Gnu.cpp

@@ -423,8 +423,12 @@ void tools::gnutools::Linker::ConstructJob(Compilation &C, const JobAction &JA,
     D.Diag(diag::err_target_unknown_triple) << Triple.str();
     return;
   }
-  if (Triple.isRISCV())
+
+  if (Triple.isRISCV()) {
     CmdArgs.push_back("-X");
+    if (Args.hasArg(options::OPT_mno_relax))
+      CmdArgs.push_back("--no-relax");
+  }
 
   const bool IsShared = Args.hasArg(options::OPT_shared);
   if (IsShared)

clang/test/Driver/riscv32-toolchain.c

@@ -231,6 +231,22 @@
 // RUN:   | FileCheck --check-prefix=CHECK-RV32-RELAX %s
 // CHECK-RV32-RELAX-NOT: "--no-relax"
 
+// Check that "--no-relax" is forwarded to the linker for RISC-V (Gnu.cpp).
+// RUN: env "PATH=" %clang -### %s -fuse-ld=ld -no-pie -mno-relax \
+// RUN:   --target=riscv32-unknown-linux-gnu --rtlib=platform --unwindlib=platform -mabi=ilp32 \
+// RUN:   --gcc-toolchain=%S/Inputs/multilib_riscv_linux_sdk \
+// RUN:   --sysroot=%S/Inputs/multilib_riscv_linux_sdk/sysroot 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-RV32-GNU-NORELAX %s
+// CHECK-RV32-GNU-NORELAX: "--no-relax"
+
+// Check that "--no-relax" is not forwarded to the linker for RISC-V (Gnu.cpp).
+// RUN: env "PATH=" %clang -### %s -fuse-ld=ld -no-pie \
+// RUN:   --target=riscv32-unknown-linux-gnu --rtlib=platform --unwindlib=platform -mabi=ilp32 \
+// RUN:   --gcc-toolchain=%S/Inputs/multilib_riscv_linux_sdk \
+// RUN:   --sysroot=%S/Inputs/multilib_riscv_linux_sdk/sysroot 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-RV32-GNU-RELAX %s
+// CHECK-RV32-GNU-RELAX-NOT: "--no-relax"
+
 typedef __builtin_va_list va_list;
 typedef __SIZE_TYPE__ size_t;
 typedef __PTRDIFF_TYPE__ ptrdiff_t;

clang/test/Driver/riscv64-toolchain.c

@@ -187,6 +187,22 @@
 // RUN:   | FileCheck --check-prefix=CHECK-RV64-RELAX %s
 // CHECK-RV64-RELAX-NOT: "--no-relax"
 
+// Check that "--no-relax" is forwarded to the linker for RISC-V (Gnu.cpp).
+// RUN: env "PATH=" %clang -### %s -fuse-ld=ld -no-pie -mno-relax \
+// RUN:   --target=riscv64-unknown-linux-gnu --rtlib=platform --unwindlib=platform -mabi=lp64 \
+// RUN:   --gcc-toolchain=%S/Inputs/multilib_riscv_linux_sdk \
+// RUN:   --sysroot=%S/Inputs/multilib_riscv_linux_sdk/sysroot 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-RV64-GNU-NORELAX %s
+// CHECK-RV64-GNU-NORELAX: "--no-relax"
+
+// Check that "--no-relax" is not forwarded to the linker for RISC-V (Gnu.cpp).
+// RUN: env "PATH=" %clang -### %s -fuse-ld=ld -no-pie \
+// RUN:   --target=riscv64-unknown-linux-gnu --rtlib=platform --unwindlib=platform -mabi=lp64 \
+// RUN:   --gcc-toolchain=%S/Inputs/multilib_riscv_linux_sdk \
+// RUN:   --sysroot=%S/Inputs/multilib_riscv_linux_sdk/sysroot 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-RV64-GNU-RELAX %s
+// CHECK-RV64-GNU-RELAX-NOT: "--no-relax"
+
 typedef __builtin_va_list va_list;
 typedef __SIZE_TYPE__ size_t;
 typedef __PTRDIFF_TYPE__ ptrdiff_t;