Here's a slightly more specific diff avoiding useless stat(2)
Index: engine.c
===================================================================
RCS file: /cvs/src/usr.bin/make/engine.c,v
retrieving revision 1.70
diff -u -p -r1.70 engine.c
--- engine.c 25 Oct 2021 19:54:29 -0000 1.70
+++ engine.c 28 May 2023 16:07:44 -0000
@@ -84,6 +84,7 @@
#include "extern.h"
#include "lst.h"
#include "timestamp.h"
+#include "main.h"
#include "make.h"
#include "pathnames.h"
#include "error.h"
@@ -210,6 +211,7 @@ node_failure(GNode *gn)
fflush(stdout);
else {
print_errors();
+ dump_unreadable();
Punt(NULL);
}
}
Index: main.c
===================================================================
RCS file: /cvs/src/usr.bin/make/main.c,v
retrieving revision 1.129
diff -u -p -r1.129 main.c
--- main.c 17 Jan 2023 13:03:22 -0000 1.129
+++ main.c 28 May 2023 16:07:45 -0000
@@ -87,6 +87,8 @@ bool ignoreErrors; /* -i flag */
bool beSilent; /* -s flag */
bool dumpData; /* -p flag */
+static LIST unreadable;
+
struct dirs {
char *current;
char *object;
@@ -826,6 +828,48 @@ main(int argc, char **argv)
return 0;
}
+struct unreadable {
+ char *fname;
+ int errcode;
+};
+
+void
+dump_unreadable(void)
+{
+ struct unreadable *u;
+
+ if (Lst_IsEmpty(&unreadable))
+ return;
+
+ fprintf(stderr, "Makefile(s) that couldn't be read:\n");
+
+ while ((u = Lst_Pop(&unreadable))) {
+ fprintf(stderr, "\t%s: %s\n", u->fname, strerror(u->errcode));
+ free(u->fname);
+ free(u);
+ }
+}
+
+static FILE *
+open_makefile(const char *fname)
+{
+ FILE *stream;
+ struct unreadable *u;
+
+ stream = fopen(fname, "r");
+ if (stream != NULL)
+ return stream;
+
+ if (errno != ENOENT) {
+ u = emalloc(sizeof *u);
+ u->fname = strdup(fname);
+ u->errcode = errno;
+ Lst_AtEnd(&unreadable, u);
+ }
+
+ return NULL;
+}
+
/*-
* ReadMakefile --
* Open and parse the given makefile.
@@ -848,14 +892,14 @@ ReadMakefile(void *p, void *q)
Var_Set("MAKEFILE", "");
Parse_File(estrdup("(stdin)"), stdin);
} else {
- if ((stream = fopen(fname, "r")) != NULL)
+ if ((stream = open_makefile(fname)) != NULL)
goto found;
/* if we've chdir'd, rebuild the path name */
if (d->current != d->object && *fname != '/') {
char *path;
path = Str_concat(d->current, fname, '/');
- if ((stream = fopen(path, "r")) == NULL)
+ if ((stream = open_makefile(path)) == NULL)
free(path);
else {
fname = path;
@@ -866,7 +910,14 @@ ReadMakefile(void *p, void *q)
name = Dir_FindFile(fname, userIncludePath);
if (!name)
name = Dir_FindFile(fname, systemIncludePath);
- if (!name || !(stream = fopen(name, "r")))
+ if (!name)
+ return false;
+ /* do not try to open a file we already have, so that
+ * dump_unreadable() yields non-confusing results.
+ */
+ if (strcmp(name, fname) == 0)
+ return false;
+ if ((stream = open_makefile(name)) == NULL)
return false;
fname = name;
/*
Index: main.h
===================================================================
RCS file: /cvs/src/usr.bin/make/main.h,v
retrieving revision 1.6
diff -u -p -r1.6 main.h
--- main.h 13 Jan 2020 14:51:50 -0000 1.6
+++ main.h 28 May 2023 16:07:45 -0000
@@ -41,4 +41,8 @@ extern Lst create;
/* set_notparallel(): used to influence running mode from parse.c */
extern void set_notparallel(void);
+/* dump_unreadable: in case of some errors, dump makefile names
+ * we found but are unable to read.
+ */
+extern void dump_unreadable(void);
#endif
Index: parse.c
===================================================================
RCS file: /cvs/src/usr.bin/make/parse.c,v
retrieving revision 1.134
diff -u -p -r1.134 parse.c
--- parse.c 6 Mar 2021 08:31:42 -0000 1.134
+++ parse.c 28 May 2023 16:07:45 -0000
@@ -1696,6 +1696,7 @@ void
Parse_MainName(Lst listmain) /* result list */
{
if (mainNode == NULL) {
+ dump_unreadable();
Punt("no target to make.");
/*NOTREACHED*/
} else if (mainNode->type & OP_DOUBLEDEP) {
