From db09161ba9ba9fe196712668c24e843c7130d0bb Mon Sep 17 00:00:00 2001
From: Junchao Zhang <jczhang@anl.gov>
Date: Fri, 28 Aug 2026 17:47:30 -0500
Subject: [PATCH] Improve f_check when assembly has no vendor identity

Vendor detection in f_check greps the probe assembly (ftest.s) for a
compiler identity string. Some compilers, notably Intel ifx, emit no
such string, so the primary `case "$data"` scan fails to set a vendor.

The name-based fallback only recognizes bare compiler names, so an
ifx-backed wrapper (e.g. mpif90, mpifort or the Cray ftn wrapper) is not
matched either, leaving the vendor empty and resulting in a false
conclusion that no Fortran compilers are available.

Append the output of `$compiler --version` to $data so such compilers
are identified by their version banner (ifx's contains "ifx", "Intel").
---
 f_check    | 3 +++
 f_check.pl | 8 ++++++--
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/f_check b/f_check
index 1501a4986e..00f2b06aea 100755
--- a/f_check
+++ b/f_check
@@ -76,6 +76,9 @@ else
     	if [ -z "$data" ]; then
     		data=`$compiler -O2 -S ftest.f > /dev/null 2>&1 && cat ftest.c && rm -f ftest.c`
     	fi
+    	# Some compilers (e.g. Intel ifx) embed no vendor identity in the assembly;
+    	# append the --version banner so the vendor detection below can match them.
+    	ver=`$compiler --version 2>&1` && data=`printf '%s\n%s' "$data" "$ver"`
 
         case "$data" in *zhoge_*) bu=_ ;; esac
 
diff --git a/f_check.pl b/f_check.pl
index 889aedd050..8a190082c9 100644
--- a/f_check.pl
+++ b/f_check.pl
@@ -19,7 +19,7 @@
 
 $compiler = join(" ", @ARGV);
 $compiler_bin = shift(@ARGV);
- 
+
 # f77 is too ambiguous
 $compiler = "" if $compiler eq "f77";
 
@@ -67,6 +67,10 @@
 	if ($data eq "") {
 		$data = `$compiler -O2 -S ftest.f > /dev/null 2>&1 && cat ftest.c && rm -f ftest.c`;
 	}
+	my $ver = `$compiler --version 2>&1`;
+	if (!$?) {
+		$data = "$data\n$ver";
+	}
 	if ($data =~ /zhoge_/) {
 	    $bu       = "_";
 	}
@@ -323,7 +327,7 @@
 if ($link ne "") {
 
     $link =~ s/\-Y\sP\,/\-Y/g;
-    
+
     $link =~ s/\-R\s*/\-rpath\%/g;
 
     $link =~ s/\-rpath\s+/\-rpath\%/g;