Fortran: Fix suprious dependencies with submodules

In commit 695f0d0d3a (cmFortranParser: Parse keywords as lexical tokens,
2016-09-05, v3.7.0-rc1~150^2) we created keyword-specific variants of
the original `USE WORD other EOSTMT` production, such as
`MODULE WORD other EOSTMT` and `INTERFACE WORD other EOSTMT`.  The same
pattern was used by more keyword-specific productions in commit b5ac8b8aa7
(Fortran: Add support for submodule syntax in dependency scanning,
2016-09-05, v3.7.0-rc1~73^2~1).

The postfix part (`other`) of several keyword-specific productions is
not needed to match Fortran syntax.  See the Fortran 2018 standard,
para.4.1.4/1 on p.28, para.14.2.1/2 on pp.293-294.  The postfix is
needed only for a case of operator 'use':

    use <module-name> [, only : <list-of-vars>]

The unnecessary postfix matching from the keyword-specific productions
such as module, submodule, and interface declarations can cause spurious
module dependencies to be detected, so remove it.

Extend the test suite with examples covering the previously-broken
cases.

Fixes: #18427

1 files changed, 7 insertions, 11 deletions

diff --git a/Source/LexerParser/cmFortranParser.y b/Source/LexerParser/cmFortranParser.y
index 07ca630..a5c8976 100644
--- a/Source/LexerParser/cmFortranParser.y
+++ b/Source/LexerParser/cmFortranParser.y
@@ -115,34 +115,30 @@ stmt:
     cmFortranParser_RuleUse(parser, $2);
     free($2);
   }
-| MODULE WORD other EOSTMT {
+| MODULE WORD EOSTMT {
     cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
-    if (cmsysString_strcasecmp($2, "function") != 0 &&
-        cmsysString_strcasecmp($2, "procedure") != 0 &&
-        cmsysString_strcasecmp($2, "subroutine") != 0) {
-      cmFortranParser_RuleModule(parser, $2);
-    }
+    cmFortranParser_RuleModule(parser, $2);
     free($2);
   }
-| SUBMODULE LPAREN WORD RPAREN WORD other EOSTMT {
+| SUBMODULE LPAREN WORD RPAREN WORD EOSTMT {
     cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
     cmFortranParser_RuleSubmodule(parser, $3, $5);
     free($3);
     free($5);
   }
-| SUBMODULE LPAREN WORD COLON WORD RPAREN WORD other EOSTMT {
+| SUBMODULE LPAREN WORD COLON WORD RPAREN WORD EOSTMT {
     cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
     cmFortranParser_RuleSubmoduleNested(parser, $3, $5, $7);
     free($3);
     free($5);
     free($7);
   }
-| INTERFACE WORD other EOSTMT {
+| INTERFACE WORD EOSTMT {
     cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
     cmFortranParser_SetInInterface(parser, true);
     free($2);
   }
-| END INTERFACE other EOSTMT {
+| END INTERFACE EOSTMT {
     cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
     cmFortranParser_SetInInterface(parser, false);
   }
@@ -163,7 +159,7 @@ stmt:
     free($3);
     free($5);
   }
-| INCLUDE STRING other EOSTMT {
+| INCLUDE STRING EOSTMT {
     cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
     cmFortranParser_RuleInclude(parser, $2);
     free($2);