2 files changed, 60 insertions, 18 deletions

diff --git a/miscutils/make.c b/miscutils/make.c
index daad75f5c..86d06e970 100644
--- a/miscutils/make.c
+++ b/miscutils/make.c
@@ -717,21 +717,23 @@ dyndep(struct name *np, struct rule *imprule)
                         sp = findname(auto_concat(newsuff, suff));
                         if (sp && sp->n_rule) {
                                 // Generate a name for an implicit prerequisite
-                                pp = newname(auto_concat(base, newsuff));
-                                if (!pp->n_tim.tv_sec)
-                                        modtime(pp);
-                                if ((!chain && (pp->n_tim.tv_sec || getcmd(pp))) ||
-                                                (chain && dyndep(pp, NULL))) {
+                                struct name *ip = newname(auto_concat(base, newsuff));
+                                if ((ip->n_flag & N_DOING))
+                                        continue;
+                                if (!ip->n_tim.tv_sec)
+                                        modtime(ip);
+                                if (chain ? ip->n_tim.tv_sec || (ip->n_flag & N_TARGET) :
+                                                        dyndep(ip, NULL) != NULL) {
                                         // Prerequisite exists or we know how to make it
                                         if (imprule) {
                                                 dp = NULL;
-                                                newdep(&dp, pp);
+                                                newdep(&dp, ip);
                                                 imprule->r_dep = dp;
                                                 imprule->r_cmd = sp->n_rule->r_cmd;
                                         }
+                                        pp = ip;
                                         goto finish;
                                 }
-                                pp = NULL;
                         }
                 }
         }
@@ -2121,6 +2123,7 @@ make(struct name *np, int level)
                 }
                 for (dp = rp->r_dep; dp; dp = dp->d_next) {
                         // Make prerequisite
+                        dp->d_name->n_flag |= N_TARGET;
                         estat |= make(dp->d_name, level + 1);
 
                         // Make strings of out-of-date prerequisites (for $?),
@@ -2166,28 +2169,28 @@ make(struct name *np, int level)
 
         if (quest) {
                 if (timespec_le(&np->n_tim, &dtim)) {
-                        clock_gettime(CLOCK_REALTIME, &np->n_tim);
-                        return 1;       // 1 means rebuild is needed
+                        didsomething = 1;
+                        estat = 1;      // 1 means rebuild is needed
                 }
         } else if (!(np->n_flag & N_DOUBLE) &&
                                 ((np->n_flag & N_PHONY) || (timespec_le(&np->n_tim, &dtim)))) {
                 if (estat == 0) {
-                        if (!sc_cmd) {
-                                if (!doinclude)
-                                        bb_error_msg("nothing to be done for %s", np->n_name);
-                        } else {
+                        if (sc_cmd)
                                 estat = make1(np, sc_cmd, oodate, allsrc, dedup, impdep);
-                                clock_gettime(CLOCK_REALTIME, &np->n_tim);
-                        }
+                        else if (!doinclude)
+                                bb_error_msg("nothing to be done for %s", np->n_name);
+                        didsomething = 1;
                 } else if (!doinclude) {
                         bb_error_msg("'%s' not built due to errors", np->n_name);
                 }
                 free(oodate);
-        } else if (didsomething) {
+        }
+
+        if (didsomething)
                 clock_gettime(CLOCK_REALTIME, &np->n_tim);
-        } else if (level == 0) {
+        else if (!quest && level == 0)
                 printf("%s: '%s' is up to date\n", applet_name, np->n_name);
-        }
+
         free(allsrc);
         free(dedup);
         return estat;
diff --git a/testsuite/make.tests b/testsuite/make.tests
index f52770438..7bb736ade 100755
--- a/testsuite/make.tests
+++ b/testsuite/make.tests
@@ -397,6 +397,45 @@ target:
         : hash # hash
 '
 
+# Austin Group defect report 875 clarifies certain aspects of the
+# behaviour of inference rules.  Study of this resulted in a number
+# of changes to pdpmake.  Since the issue at hand involves the use
+# of chained inference rules it doesn't affect POSIX mode.
+mkdir make.tempdir && cd make.tempdir || exit 1
+touch test.j test.k
+testing "make proper handling of inference rules 1" \
+        "make -f -" \
+        ".j.l\n" "" '
+.SUFFIXES: .j .k .l
+.j.l:
+        @echo .j.l
+.k.l:
+        @echo .k.l
+test.l: test.k
+test.j:
+test.k:
+'
+cd .. || exit 1; rm -rf make.tempdir 2>/dev/null
+
+# The actual test in the above-mentioned defect report was actually
+# more demanding.  It used the suffixes '.a .b .c'.  This results in
+# the built-in '.c.a' inference rule being introduced into the mix.
+mkdir make.tempdir && cd make.tempdir || exit 1
+touch test.a test.b
+testing "make proper handling of inference rules 2" \
+        "make -f -" \
+        ".a.c\n" "" '
+.SUFFIXES: .a .b .c
+.a.c:
+        @echo .a.c
+.b.c:
+        @echo .b.c
+test.c: test.b
+test.a:
+test.b:
+'
+cd .. || exit 1; rm -rf make.tempdir 2>/dev/null
+
 # Skip duplicate entries in $? and $^
 mkdir make.tempdir && cd make.tempdir || exit 1
 touch -t 202206171200 file1 file3