[Driver][test] Make RISCV tests robust with PATH=

[sunshaoce]

Summary

When riscv64-unknown-linux-gnu-ld is in the PATH, clang -### -fuse-ld=ld --target=riscv64-unknown-linux-gnu will use unknown-linux-gnu-ld first, which causes the error in the lit test.

[StephenFan]

Why not use env PATH= in the lit run line to clear the PATH env variable?

[sunshaoce]

Address @StephenFan's comment.

[MaskRay]

unknown-linux-gnu-ld

riscv64-unknown-linux-gnu-ld.

Please update your local commit message. I changed the patch's subject.

clang/test/Driver/riscv64-toolchain.c

 // RUN: %clang -### %s --target=riscv32 -fuse-ld=lld \
 // RUN:   --gcc-toolchain=%S/Inputs/basic_riscv64_tree 2>&1 \
 // RUN:   | FileCheck -check-prefix=LLD %s
 // LLD: {{(error: invalid linker name in argument '-fuse-ld=lld')|(ld.lld)}}
 
 // In the below tests, --rtlib=platform is used so that the driver ignores
 // the configure-time CLANG_DEFAULT_RTLIB option when choosing the runtime lib
 
-// RUN: %clang -### %s -fuse-ld= \
+// RUN: env "PATH=" %clang -### %s -fuse-ld= \
 // RUN:   --target=riscv64-unknown-elf --rtlib=platform \
 // RUN:   --gcc-toolchain=%S/Inputs/basic_riscv64_tree \
 // RUN:   --sysroot=%S/Inputs/basic_riscv64_tree/riscv64-unknown-elf 2>&1 -no-pie \
 // RUN:   | FileCheck -check-prefix=C-RV64-BAREMETAL-LP64 %s
 
 // C-RV64-BAREMETAL-LP64: "{{.*}}Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}riscv64-unknown-elf-ld"
 // C-RV64-BAREMETAL-LP64: "--sysroot={{.*}}/Inputs/basic_riscv64_tree/riscv64-unknown-elf"
 // C-RV64-BAREMETAL-LP64: "{{.*}}/Inputs/basic_riscv64_tree/riscv64-unknown-elf/lib{{/|\\\\}}crt0.o"
 // C-RV64-BAREMETAL-LP64: "{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1{{/|\\\\}}crtbegin.o"
 // C-RV64-BAREMETAL-LP64: "-L{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1"
 // C-RV64-BAREMETAL-LP64: "-L{{.*}}/Inputs/basic_riscv64_tree/riscv64-unknown-elf/lib"
 // C-RV64-BAREMETAL-LP64: "--start-group" "-lc" "-lgloss" "--end-group" "-lgcc"
 // C-RV64-BAREMETAL-LP64: "{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1{{/|\\\\}}crtend.o"
 
-// RUN: %clang -### %s -fuse-ld= \
+// RUN: env "PATH=" %clang -### %s -fuse-ld= \
 // RUN:   --target=riscv64-unknown-elf --rtlib=platform \
 // RUN:   --sysroot= \
 // RUN:   --gcc-toolchain=%S/Inputs/basic_riscv64_tree 2>&1 \
 // RUN:   | FileCheck -check-prefix=C-RV64-BAREMETAL-NOSYSROOT-LP64 %s
 
 // C-RV64-BAREMETAL-NOSYSROOT-LP64: "{{.*}}Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}riscv64-unknown-elf-ld"
 // C-RV64-BAREMETAL-NOSYSROOT-LP64: "{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1/../../..{{/|\\\\}}..{{/|\\\\}}riscv64-unknown-elf/lib{{/|\\\\}}crt0.o"
 // C-RV64-BAREMETAL-NOSYSROOT-LP64: "{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1{{/|\\\\}}crtbegin.o"
 // C-RV64-BAREMETAL-NOSYSROOT-LP64: "-L{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1"
 // C-RV64-BAREMETAL-NOSYSROOT-LP64: "-L{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1/../../..{{/|\\\\}}..{{/|\\\\}}riscv64-unknown-elf{{/|\\\\}}lib"
 // C-RV64-BAREMETAL-NOSYSROOT-LP64: "--start-group" "-lc" "-lgloss" "--end-group" "-lgcc"
 // C-RV64-BAREMETAL-NOSYSROOT-LP64: "{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1{{/|\\\\}}crtend.o"
 
-// RUN: %clangxx -### %s -fuse-ld= \
+// RUN: env "PATH=" %clangxx -### %s -fuse-ld= \
 // RUN:   --target=riscv64-unknown-elf -stdlib=libstdc++ --rtlib=platform \
 // RUN:   --gcc-toolchain=%S/Inputs/basic_riscv64_tree \
 // RUN:   --sysroot=%S/Inputs/basic_riscv64_tree/riscv64-unknown-elf 2>&1 \
 // RUN:   | FileCheck -check-prefix=CXX-RV64-BAREMETAL-LP64 %s
 
 // CXX-RV64-BAREMETAL-LP64: "-internal-isystem" "{{.*}}Inputs/basic_riscv64_tree/riscv64-unknown-elf/include/c++{{/|\\\\}}8.0.1"
 // CXX-RV64-BAREMETAL-LP64: "{{.*}}Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}riscv64-unknown-elf-ld"
 // CXX-RV64-BAREMETAL-LP64: "--sysroot={{.*}}/Inputs/basic_riscv64_tree/riscv64-unknown-elf"
 // CXX-RV64-BAREMETAL-LP64: "{{.*}}/Inputs/basic_riscv64_tree/riscv64-unknown-elf/lib{{/|\\\\}}crt0.o"
 // CXX-RV64-BAREMETAL-LP64: "{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1{{/|\\\\}}crtbegin.o"
 // CXX-RV64-BAREMETAL-LP64: "-L{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1"
 // CXX-RV64-BAREMETAL-LP64: "-L{{.*}}/Inputs/basic_riscv64_tree/riscv64-unknown-elf/lib"
 // CXX-RV64-BAREMETAL-LP64: "-lstdc++" "--start-group" "-lc" "-lgloss" "--end-group" "-lgcc"
 // CXX-RV64-BAREMETAL-LP64: "{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1{{/|\\\\}}crtend.o"
 
-// RUN: %clangxx -### %s -fuse-ld= \
+// RUN: env "PATH=" %clangxx -### %s -fuse-ld= \
 // RUN:   --target=riscv64-unknown-elf -stdlib=libstdc++ --rtlib=platform \
 // RUN:   --sysroot= \
 // RUN:   --gcc-toolchain=%S/Inputs/basic_riscv64_tree 2>&1 \
 // RUN:   | FileCheck -check-prefix=CXX-RV64-BAREMETAL-NOSYSROOT-LP64 %s
 
 // CXX-RV64-BAREMETAL-NOSYSROOT-LP64: "-internal-isystem" "{{.*}}Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1/../../..{{/|\\\\}}..{{/|\\\\}}riscv64-unknown-elf/include/c++{{/|\\\\}}8.0.1"
 // CXX-RV64-BAREMETAL-NOSYSROOT-LP64: "{{.*}}Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1/../../..{{/|\\\\}}..{{/|\\\\}}bin{{/|\\\\}}riscv64-unknown-elf-ld"
 // CXX-RV64-BAREMETAL-NOSYSROOT-LP64: "{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1/../../..{{/|\\\\}}..{{/|\\\\}}riscv64-unknown-elf/lib{{/|\\\\}}crt0.o"
 // CXX-RV64-BAREMETAL-NOSYSROOT-LP64: "{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1{{/|\\\\}}crtbegin.o"
 // CXX-RV64-BAREMETAL-NOSYSROOT-LP64: "-L{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1"
 // CXX-RV64-BAREMETAL-NOSYSROOT-LP64: "-L{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1/../../..{{/|\\\\}}..{{/|\\\\}}riscv64-unknown-elf/lib"
 // CXX-RV64-BAREMETAL-NOSYSROOT-LP64: "-lstdc++" "--start-group" "-lc" "-lgloss" "--end-group" "-lgcc"
 // CXX-RV64-BAREMETAL-NOSYSROOT-LP64: "{{.*}}/Inputs/basic_riscv64_tree/lib/gcc/riscv64-unknown-elf/8.0.1{{/|\\\\}}crtend.o"
 
-// RUN: %clang -### %s -fuse-ld= -no-pie \
+// RUN: env "PATH=" %clang -### %s -fuse-ld= -no-pie \
 // RUN:   --target=riscv64-unknown-linux-gnu --rtlib=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=C-RV64-LINUX-MULTI-LP64 %s
 
 // C-RV64-LINUX-MULTI-LP64: "{{.*}}/Inputs/multilib_riscv_linux_sdk/lib/gcc/riscv64-unknown-linux-gnu/7.2.0/../../..{{/|\\\\}}..{{/|\\\\}}riscv64-unknown-linux-gnu/bin{{/|\\\\}}ld"
 // C-RV64-LINUX-MULTI-LP64: "--sysroot={{.*}}/Inputs/multilib_riscv_linux_sdk/sysroot"
 // C-RV64-LINUX-MULTI-LP64: "-m" "elf64lriscv"
 // C-RV64-LINUX-MULTI-LP64: "-dynamic-linker" "/lib/ld-linux-riscv64-lp64.so.1"
 // C-RV64-LINUX-MULTI-LP64: "{{.*}}/Inputs/multilib_riscv_linux_sdk/lib/gcc/riscv64-unknown-linux-gnu/7.2.0/lib64/lp64{{/|\\\\}}crtbegin.o"
 // C-RV64-LINUX-MULTI-LP64: "-L{{.*}}/Inputs/multilib_riscv_linux_sdk/lib/gcc/riscv64-unknown-linux-gnu/7.2.0/lib64/lp64"
 // C-RV64-LINUX-MULTI-LP64: "-L{{.*}}/Inputs/multilib_riscv_linux_sdk/sysroot/lib64/lp64"
 // C-RV64-LINUX-MULTI-LP64: "-L{{.*}}/Inputs/multilib_riscv_linux_sdk/sysroot/usr/lib64/lp64"
 
-// RUN: %clang -### %s -fuse-ld=ld -no-pie \
+// RUN: env "PATH=" %clang -### %s -fuse-ld=ld -no-pie \
 // RUN:   --target=riscv64-unknown-linux-gnu --rtlib=platform -march=rv64imafd \
 // RUN:   --gcc-toolchain=%S/Inputs/multilib_riscv_linux_sdk \
 // RUN:   --sysroot=%S/Inputs/multilib_riscv_linux_sdk/sysroot 2>&1 \
 // RUN:   | FileCheck -check-prefix=C-RV64-LINUX-MULTI-LP64D %s
 
 // C-RV64-LINUX-MULTI-LP64D: "{{.*}}/Inputs/multilib_riscv_linux_sdk/lib/gcc/riscv64-unknown-linux-gnu/7.2.0/../../..{{/|\\\\}}..{{/|\\\\}}riscv64-unknown-linux-gnu/bin{{/|\\\\}}ld"
 // C-RV64-LINUX-MULTI-LP64D: "--sysroot={{.*}}/Inputs/multilib_riscv_linux_sdk/sysroot"
 // C-RV64-LINUX-MULTI-LP64D: "-m" "elf64lriscv"