From 043b2cbb7c99d69a373f3ecbf35bc3b4638bcf85 Mon Sep 17 00:00:00 2001
From: Kyle Gerheiser <3209794+kgerheiser@users.noreply.github.com>
Date: Fri, 17 Jun 2022 16:01:49 -0400
Subject: Fix external compiler detection for MPICH and OpenMPI (#30875)

os.path.dirname was being used to compare compilers. If two compilers
are in the same directory then it will pick up the first one it encounters.

Compare the full compiler path instead.
---
 var/spack/repos/builtin/packages/mpich/package.py   | 17 +++++++++--------
 var/spack/repos/builtin/packages/openmpi/package.py | 12 ++++++------
 2 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/var/spack/repos/builtin/packages/mpich/package.py b/var/spack/repos/builtin/packages/mpich/package.py
index 2b8f9a435d..a66023734a 100644
--- a/var/spack/repos/builtin/packages/mpich/package.py
+++ b/var/spack/repos/builtin/packages/mpich/package.py
@@ -239,13 +239,13 @@ with '-Wl,-commons,use_dylibs' and without
 
     @classmethod
     def determine_variants(cls, exes, version):
-        def get_spack_compiler_spec(path):
-            spack_compilers = spack.compilers.find_compilers([path])
+        def get_spack_compiler_spec(compiler):
+            spack_compilers = spack.compilers.find_compilers(
+                [os.path.dirname(compiler)])
             actual_compiler = None
             # check if the compiler actually matches the one we want
             for spack_compiler in spack_compilers:
-                if (spack_compiler.cc and
-                        os.path.dirname(spack_compiler.cc) == path):
+                if (spack_compiler.cc and spack_compiler.cc == compiler):
                     actual_compiler = spack_compiler
                     break
             return actual_compiler.spec if actual_compiler else None
@@ -328,10 +328,11 @@ with '-Wl,-commons,use_dylibs' and without
                 variants += '+hcoll'
 
             match = re.search(r'MPICH CC:\s+(\S+)', output)
-            compiler_spec = get_spack_compiler_spec(
-                os.path.dirname(match.group(1)))
-            if compiler_spec:
-                variants.append('%' + str(compiler_spec))
+            if match:
+                compiler = match.group(1)
+                compiler_spec = get_spack_compiler_spec(compiler)
+                if compiler_spec:
+                    variants.append('%' + str(compiler_spec))
             results.append(' '.join(variants))
         return results
 
diff --git a/var/spack/repos/builtin/packages/openmpi/package.py b/var/spack/repos/builtin/packages/openmpi/package.py
index 9274c951b8..7072581201 100644
--- a/var/spack/repos/builtin/packages/openmpi/package.py
+++ b/var/spack/repos/builtin/packages/openmpi/package.py
@@ -520,8 +520,8 @@ class Openmpi(AutotoolsPackage, CudaPackage):
             # Get the appropriate compiler
             match = re.search(r'\bC compiler absolute: (\S+)', output)
             if match:
-                compiler_spec = get_spack_compiler_spec(
-                    os.path.dirname(match.group(1)))
+                compiler = match.group(1)
+                compiler_spec = get_spack_compiler_spec(compiler)
                 if compiler_spec:
                     variants.append("%" + str(compiler_spec))
             results.append(' '.join(variants))
@@ -1053,13 +1053,13 @@ class Openmpi(AutotoolsPackage, CudaPackage):
         self._test_examples()
 
 
-def get_spack_compiler_spec(path):
-    spack_compilers = spack.compilers.find_compilers([path])
+def get_spack_compiler_spec(compiler):
+    spack_compilers = spack.compilers.find_compilers(
+        [os.path.dirname(compiler)])
     actual_compiler = None
     # check if the compiler actually matches the one we want
     for spack_compiler in spack_compilers:
-        if (spack_compiler.cc and
-                os.path.dirname(spack_compiler.cc) == path):
+        if (spack_compiler.cc and spack_compiler.cc == compiler):
             actual_compiler = spack_compiler
             break
     return actual_compiler.spec if actual_compiler else None
-- 
cgit v1.2.3-70-g09d2