[flang-commits] [clang] [flang] [driver] Generalize the code that adds the path of libflang_rt.runtime.a. (PR #134362)

[Slava Zakharin via flang-commits]

================
@@ -7,35 +7,100 @@
 !! LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON, use 
 !! resource_dir_with_per_target_subdir as inputs.
 
-! Check powerpc64-ibm-aix 64-bit linking to static flang-rt
-! RUN: %flang %s -### 2>&1 \
+! Check powerpc64-ibm-aix 64-bit linking to static flang-rt by default
+! RUN: %flang -Werror %s -### 2>&1 \
 ! RUN:        --target=powerpc64-ibm-aix \
 ! RUN:        -resource-dir=%S/../../../clang/test/Driver/Inputs/resource_dir_with_per_target_subdir \
-! RUN:   | FileCheck %s --check-prefix=AIX64-LD-PER-TARGET
+! RUN:   | FileCheck %s --check-prefix=AIX64-LD-PER-TARGET-DEFAULT
 
-! AIX64-LD-PER-TARGET-NOT: warning:
-! AIX64-LD-PER-TARGET:     "-fc1" "-triple" "powerpc64-ibm-aix"
-! AIX64-LD-PER-TARGET-SAME:     "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
-! AIX64-LD-PER-TARGET:     "{{.*}}ld{{(.exe)?}}"
-! AIX64-LD-PER-TARGET-NOT: "-bnso"
-! AIX64-LD-PER-TARGET-SAME:     "-b64"
-! AIX64-LD-PER-TARGET-SAME:     "-bpT:0x100000000" "-bpD:0x110000000"
-! AIX64-LD-PER-TARGET-SAME:     "-lc"
-! AIX64-LD-PER-TARGET-SAME:     "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}powerpc64-ibm-aix{{/|\\\\}}libflang_rt.runtime.a"
-! AIX64-LD-PER-TARGET-SAME:     "-lm"
-! AIX64-LD-PER-TARGET-SAME:     "-lpthread"
-
-! Check powerpc64le-unknown-linux-gnu 64-bit linking to static flang-rt
-! RUN: %flang %s -### 2>&1 \
+! AIX64-LD-PER-TARGET-DEFAULT:     "-fc1" "-triple" "powerpc64-ibm-aix"
+! AIX64-LD-PER-TARGET-DEFAULT-SAME:     "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
+! AIX64-LD-PER-TARGET-DEFAULT:     "{{.*}}ld{{(.exe)?}}"
+! AIX64-LD-PER-TARGET-DEFAULT-NOT: "-bnso"
+! AIX64-LD-PER-TARGET-DEFAULT-SAME:     "-b64"
+! AIX64-LD-PER-TARGET-DEFAULT-SAME:     "-bpT:0x100000000" "-bpD:0x110000000"
+! AIX64-LD-PER-TARGET-DEFAULT-SAME:     "-lc"
+! AIX64-LD-PER-TARGET-DEFAULT-SAME:     "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}powerpc64-ibm-aix{{/|\\\\}}libflang_rt.runtime.a"
+! AIX64-LD-PER-TARGET-DEFAULT-SAME:     "-lm"
+! AIX64-LD-PER-TARGET-DEFAULT-SAME:     "-lpthread"
+
+
+! Check powerpc64-ibm-aix 64-bit linking to static flang-rt by option 
+! RUN: %flang -static-libflangrt -Werror %s -### 2>&1 \
+! RUN:        --target=powerpc64-ibm-aix \
+! RUN:        -resource-dir=%S/../../../clang/test/Driver/Inputs/resource_dir_with_per_target_subdir \
+! RUN:   | FileCheck %s --check-prefix=AIX64-LD-PER-TARGET-STATIC
+
+! AIX64-LD-PER-TARGET-STATIC:     "-fc1" "-triple" "powerpc64-ibm-aix"
+! AIX64-LD-PER-TARGET-STATIC-SAME:     "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
+! AIX64-LD-PER-TARGET-STATIC:     "{{.*}}ld{{(.exe)?}}"
+! AIX64-LD-PER-TARGET-STATIC-NOT: "-bnso"
+! AIX64-LD-PER-TARGET-STATIC-SAME:     "-b64"
+! AIX64-LD-PER-TARGET-STATIC-SAME:     "-bpT:0x100000000" "-bpD:0x110000000"
+! AIX64-LD-PER-TARGET-STATIC-SAME:     "-lc"
+! AIX64-LD-PER-TARGET-STATIC-SAME:     "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}powerpc64-ibm-aix{{/|\\\\}}libflang_rt.runtime.a"
+! AIX64-LD-PER-TARGET-STATIC-SAME:     "-lm"
+! AIX64-LD-PER-TARGET-STATIC-SAME:     "-lpthread"
+
+
+! Check powerpc64-ibm-aix 64-bit linking to shared flang-rt by option 
+! RUN: %flang -shared-libflangrt -Werror %s -### 2>&1 \
+! RUN:        --target=powerpc64-ibm-aix \
+! RUN:        -resource-dir=%S/../../../clang/test/Driver/Inputs/resource_dir_with_per_target_subdir \
+! RUN:   | FileCheck %s --check-prefix=AIX64-LD-PER-TARGET-SHARED
+
+! AIX64-LD-PER-TARGET-SHARED:     "-fc1" "-triple" "powerpc64-ibm-aix"
+! AIX64-LD-PER-TARGET-SHARED-SAME:     "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
+! AIX64-LD-PER-TARGET-SHARED:     "{{.*}}ld{{(.exe)?}}"
+! AIX64-LD-PER-TARGET-SHARED-NOT: "-bnso"
+! AIX64-LD-PER-TARGET-SHARED-SAME:     "-b64"
+! AIX64-LD-PER-TARGET-SHARED-SAME:     "-bpT:0x100000000" "-bpD:0x110000000"
+! AIX64-LD-PER-TARGET-SHARED-SAME:     "-lc"
+! AIX64-LD-PER-TARGET-SHARED-SAME:     "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}powerpc64-ibm-aix{{/|\\\\}}libflang_rt.runtime.a"
+! AIX64-LD-PER-TARGET-SHARED-SAME:     "-lm"
+! AIX64-LD-PER-TARGET-SHARED-SAME:     "-lpthread"
+
+
+! Check powerpc64le-unknown-linux-gnu 64-bit linking to shared flang-rt by default
+! RUN: %flang -Werror %s -### 2>&1 \
 ! RUN:        --target=powerpc64le-unknown-linux-gnu \
 ! RUN:        -resource-dir=%S/../../../clang/test/Driver/Inputs/resource_dir_with_per_target_subdir \
-! RUN:   | FileCheck %s --check-prefixes=LOP64-LD-PER-TARGET
-
-! LOP64-LD-PER-TARGET-NOT: warning:
-! LOP64-LD-PER-TARGET:     "-fc1" "-triple" "powerpc64le-unknown-linux-gnu"
-! LOP64-LD-PER-TARGET-SAME:     "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
-! LOP64-LD-PER-TARGET:     "{{.*}}ld{{(.exe)?}}"
-! LOP64-LD-PER-TARGET-NOT: "-bnso"
-! LOP64-LD-PER-TARGET-SAME:     "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}powerpc64le-unknown-linux-gnu{{/|\\\\}}libflang_rt.runtime.a"
-! LOP64-LD-PER-TARGET-SAME:     "-lm"
-! LOP64-LD-PER-TARGET-SAME:     "-lc"
+! RUN:   | FileCheck %s --check-prefixes=LOP64-LD-PER-TARGET-DEFAULT
+
+! LOP64-LD-PER-TARGET-DEFAULT:     "-fc1" "-triple" "powerpc64le-unknown-linux-gnu"
+! LOP64-LD-PER-TARGET-DEFAULT-SAME:     "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
+! LOP64-LD-PER-TARGET-DEFAULT:     "{{.*}}ld{{(.exe)?}}"
+! LOP64-LD-PER-TARGET-DEFAULT-NOT: "-bnso"
+! LOP64-LD-PER-TARGET-DEFAULT-SAME:     "[[RESOURCE_DIR]]{{/|\\\\}}lib{{/|\\\\}}powerpc64le-unknown-linux-gnu{{/|\\\\}}libflang_rt.runtime.so"
----------------
vzakhari wrote:

> This may not be an issue at least on Linux. No matter if it is `-lflang_rt.runtime` or the full path to `libflang_rt.runtime.so`, users still need to use either `LD_LIBRARY_PATH` or `-rpath` to specify where the library is at loading time. As long as it points to the correct path after relocation, it should be OK. The path specified by `-rpath` is written into the executable. I am not sure about other platforms though.

Yes, it does matter whether it is `-lflang_rt.runtime` or the full path to `linbflang_rt.runtime.so`.   Here is an example:

```
$ cat mylib.c
void in_shared_lib() {}
$ cat test.c
extern void in_shared_lib();

int main() {
  in_shared_lib();
  return 0;
}
$ clang -shared mylib.c -o libmy.so
$ clang test.c /tmp/libmy.so
$ ldd a.out
        linux-vdso.so.1 (0x00007ffedf5d9000)
        /tmp/libmy.so (0x00007fbbee17a000)
        libc.so.6 => /lib64/libc.so.6 (0x00007fbbedb81000)
        /lib64/ld-linux-x86-64.so.2 (0x00007fbbedf57000)
$ ./a.out
$ mkdir -p mylibs
$ mv libmy.so mylibs/
$ ./a.out
./a.out: error while loading shared libraries: /tmp/libmy.so: cannot open shared object file: No such file or directory
$ LD_LIBRARY_PATH=/tmp/mylibs:$LD_LIBRARY_PATH ./a.out
./a.out: error while loading shared libraries: /tmp/libmy.so: cannot open shared object file: No such file or directory
```

As I said, the dynamic linker will only look for the library at the original full path. Neither `rpath` nor `LD_LIBRARY_PATH` will affect the lookup.

https://github.com/llvm/llvm-project/pull/134362