PING [C PATCH - backport 12] Fix ICE related to implicit access attributes for VLA arguments [PR105660]

[Martin Uecker <uecker@tugraz.at>]

Ok for 12.3 ? 

Am Mittwoch, dem 19.04.2023 um 18:39 +0200 schrieb Martin Uecker:
> Ok to cherrypick for 12?   It is in GCC 13 and fixes an
> annoying ICE.
> 
> Martin
> 
> 
> 
> Here is a fix for PR105660.
> 
> Bootstrapped and regression tested on x86-64.
> 
> 
>     Fix ICE related to implicit access attributes for VLA arguments [PR105660]
>     
> 
>     When constructing the specifier string when merging an access attribute
>     that encodes information about VLA arguments, the string was constructed
>     in random order by iterating through a hash table. Fix this by iterating
>     though the list of arguments.
>     
> 
>     PR c/105660
>     
> 
>     gcc/Changelog
>             * c-family/c-attribs.cc (append_access_attr): Use order
>             of arguments when construction string.
>             (append_access_attr_idxs): Rename and make static.
>             * c-familty/c-warn.cc (warn_parm_array_mismatch): Add assertion.
>     
> 
>     gcc/testsuite/ChangeLog:
>             * gcc.dg/pr105660-1.c: New test.
>             * gcc.dg/pr105660-2.c: New test.
> 
> 
> diff --git a/gcc/c-family/c-attribs.cc b/gcc/c-family/c-attribs.cc
> index 4667f6de311..072cfb69147 100644
> --- a/gcc/c-family/c-attribs.cc
> +++ b/gcc/c-family/c-attribs.cc
> @@ -4728,22 +4728,27 @@ append_access_attr (tree node[3], tree attrs, const char *attrstr,
>    rdwr_map cur_idxs;
>    init_attr_rdwr_indices (&cur_idxs, attrs);
>  
> 
> +  tree args = TYPE_ARG_TYPES (node[0]);
> +  int argpos = 0;
>    std::string spec;
> -  for (auto it = new_idxs.begin (); it != new_idxs.end (); ++it)
> +  for (tree arg = args; arg; arg = TREE_CHAIN (arg), argpos++)
>      {
> -      const auto &newaxsref = *it;
> +      const attr_access* const newa = new_idxs.get (argpos);
> +
> +      if (!newa)
> +	continue;
>  
> 
>        /* The map has two equal entries for each pointer argument that
>  	 has an associated size argument.  Process just the entry for
>  	 the former.  */
> -      if ((unsigned)newaxsref.first != newaxsref.second.ptrarg)
> +      if ((unsigned)argpos != newa->ptrarg)
>  	continue;
>  
> 
> -      const attr_access* const cura = cur_idxs.get (newaxsref.first);
> +      const attr_access* const cura = cur_idxs.get (argpos);
>        if (!cura)
>  	{
>  	  /* The new attribute needs to be added.  */
> -	  tree str = newaxsref.second.to_internal_string ();
> +	  tree str = newa->to_internal_string ();
>  	  spec += TREE_STRING_POINTER (str);
>  	  continue;
>  	}
> @@ -4751,7 +4756,6 @@ append_access_attr (tree node[3], tree attrs, const char *attrstr,
>        /* The new access spec refers to an array/pointer argument for
>  	 which an access spec already exists.  Check and diagnose any
>  	 conflicts.  If no conflicts are found, merge the two.  */
> -      const attr_access* const newa = &newaxsref.second;
>  
> 
>        if (!attrstr)
>  	{
> @@ -4886,7 +4890,7 @@ append_access_attr (tree node[3], tree attrs, const char *attrstr,
>  	continue;
>  
> 
>        /* Merge the CURA and NEWA.  */
> -      attr_access merged = newaxsref.second;
> +      attr_access merged = *newa;
>  
> 
>        /* VLA seen in a declaration takes precedence.  */
>        if (cura->minsize == HOST_WIDE_INT_M1U)
> @@ -4912,9 +4916,9 @@ append_access_attr (tree node[3], tree attrs, const char *attrstr,
>  
> 
>  /* Convenience wrapper for the above.  */
>  
> 
> -tree
> -append_access_attr (tree node[3], tree attrs, const char *attrstr,
> -		    char code, HOST_WIDE_INT idxs[2])
> +static tree
> +append_access_attr_idxs (tree node[3], tree attrs, const char *attrstr,
> +			 char code, HOST_WIDE_INT idxs[2])
>  {
>    char attrspec[80];
>    int n = sprintf (attrspec, "%c%u", code, (unsigned) idxs[0] - 1);
> @@ -5204,7 +5208,7 @@ handle_access_attribute (tree node[3], tree name, tree args, int flags,
>       attributes specified on previous declarations of the same type
>       and if not, concatenate the two.  */
>    const char code = attr_access::mode_chars[mode];
> -  tree new_attrs = append_access_attr (node, attrs, attrstr, code, idxs);
> +  tree new_attrs = append_access_attr_idxs (node, attrs, attrstr, code, idxs);
>    if (!new_attrs)
>      return NULL_TREE;
>  
> 
> @@ -5217,7 +5221,7 @@ handle_access_attribute (tree node[3], tree name, tree args, int flags,
>      {
>        /* Repeat for the previously declared type.  */
>        attrs = TYPE_ATTRIBUTES (TREE_TYPE (node[1]));
> -      new_attrs = append_access_attr (node, attrs, attrstr, code, idxs);
> +      new_attrs = append_access_attr_idxs (node, attrs, attrstr, code, idxs);
>        if (!new_attrs)
>  	return NULL_TREE;
>  
> 
> diff --git a/gcc/c-family/c-warn.cc b/gcc/c-family/c-warn.cc
> index 29efce3f2c0..a6fb95b1e80 100644
> --- a/gcc/c-family/c-warn.cc
> +++ b/gcc/c-family/c-warn.cc
> @@ -3617,6 +3617,8 @@ warn_parm_array_mismatch (location_t origloc, tree fndecl, tree newparms)
>        for (tree newvbl = newa->size, curvbl = cura->size; newvbl;
>  	   newvbl = TREE_CHAIN (newvbl), curvbl = TREE_CHAIN (curvbl))
>  	{
> +	  gcc_assert (curvbl);
> +
>  	  tree newpos = TREE_PURPOSE (newvbl);
>  	  tree curpos = TREE_PURPOSE (curvbl);
>  
> 
> diff --git a/gcc/testsuite/gcc.dg/pr105660-1.c b/gcc/testsuite/gcc.dg/pr105660-1.c
> new file mode 100644
> index 00000000000..d4454f04c43
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/pr105660-1.c
> @@ -0,0 +1,13 @@
> +/* PR105660
> + * { dg-do compile }
> + * { dg-options "-std=c17" }
> + */
> +
> +void gatherConservativeVars(int, int, int, int, int, int, int Hnvar, int,
> +                            int Hnyt, int Hnxyt, int, int Hstep, double[Hnyt],
> +                            double[Hnvar][Hstep][Hnxyt]);
> +void gatherConservativeVars(int, int, int, int, int, int, int Hnvar, int, int Hnyt,
> +                            int Hnxyt, int, int Hstep, double[Hnyt],
> +                            double[Hnvar][Hstep][Hnxyt]);
> +
> +
> diff --git a/gcc/testsuite/gcc.dg/pr105660-2.c b/gcc/testsuite/gcc.dg/pr105660-2.c
> new file mode 100644
> index 00000000000..29fd82f923b
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/pr105660-2.c
> @@ -0,0 +1,12 @@
> +/* PR105660
> + * { dg-do compile }
> + * { dg-options "-Wall -std=c17" }
> + */
> +
> +
> +struct bat_gen_conf_s;
> +void batch_generator_create2(struct bat_gen_conf_s* config, int D, int N, const long bat_dims[D][N], const long tot_dims[D][N], const long tot_strs[D][N], const _Complex float* data[D]);
> +void batch_generator_create2(struct bat_gen_conf_s* config, int D, int N, const long bat_dims[D][N], const long tot_dims[D][N], const long tot_strs[D][N], const _Complex float* data[D]);
> +
> +
> +
> 
>