Re: Request for better syntax checking in lang.opt

["Martin Liška" <mliska@suse.cz>]

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On 2/20/20 7:08 PM, Thomas Koenig wrote:
> Hi Martin,
> 
>> Sure, I can improve sanity checking.
> 
> Thanks!
> 
>> What exactly have you screwed up?
> I had, in lang.opt
> 
> EnumValue
> Enum (gfc_fcoarray) String (native) Value (GFC_FCOARRAY_NATIVE)
> 
> It was a bit non-obvious to me that this led to the whole sub-option
> being ignored due to
> 
> *drum roll*
> 
> the space between the keywords and the opening parenthesis.  I have
> internalized the GNU style guides to such an extent that I hardly
> ever see the space there :-)

Hello.

I was able to write a sanity check for these kind of issues, but it does
not resolve all similar issues for other keywords. It's not easy to do it.

Martin

> 
> Regards
> 
>      Thomas


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From 440fda0ccd2211cfd0478f50cc20d0969fe8bce0 Mon Sep 17 00:00:00 2001
From: Martin Liska <mliska@suse.cz>
Date: Fri, 21 Feb 2020 10:40:57 +0100
Subject: [PATCH] Make more sanity checks for enums.

---
 gcc/opt-functions.awk | 13 +++++++++++++
 gcc/opt-read.awk      | 10 +++++-----
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/gcc/opt-functions.awk b/gcc/opt-functions.awk
index 2f0442dc563..be4b9e66165 100644
--- a/gcc/opt-functions.awk
+++ b/gcc/opt-functions.awk
@@ -72,6 +72,19 @@ function opt_args(name, flags)
 	return flags
 }
 
+# If FLAGS contains a "NAME(...argument...)" flag, return the value
+# of the argument.  Print error message otherwise.
+function opt_args_non_empty(name, flags, description)
+{
+	args = opt_args(name, flags)
+	if (args == "")
+	{
+		print "Empty option argument '" name "' during parsing of: " flags >> "/dev/stderr"
+		exit 1
+	}
+	return args
+}
+
 # Return the Nth comma-separated element of S.  Return the empty string
 # if S does not contain N elements.
 function nth_arg(n, s)
diff --git a/gcc/opt-read.awk b/gcc/opt-read.awk
index a2e16f29aff..9bb9dfcf6ca 100644
--- a/gcc/opt-read.awk
+++ b/gcc/opt-read.awk
@@ -81,8 +81,8 @@ BEGIN {
 		}
 		else if ($1 == "Enum") {
 			props = $2
-			name = opt_args("Name", props)
-			type = opt_args("Type", props)
+			name = opt_args_non_empty("Name", props)
+			type = opt_args_non_empty("Type", props)
 			unknown_error = opt_args("UnknownError", props)
 			enum_names[n_enums] = name
 			enum_type[name] = type
@@ -93,9 +93,9 @@ BEGIN {
 		}
 		else if ($1 == "EnumValue")  {
 			props = $2
-			enum_name = opt_args("Enum", props)
-			string = opt_args("String", props)
-			value = opt_args("Value", props)
+			enum_name = opt_args_non_empty("Enum", props)
+			string = opt_args_non_empty("String", props)
+			value = opt_args_non_empty("Value", props)
 			val_flags = "0"
 			val_flags = val_flags \
 			  test_flag("Canonical", props, "| CL_ENUM_CANONICAL") \
-- 
2.25.0