make: fix typo in inference rule handling

A typo in the previous commit caused dyndep() to process inference
rules incorrectly.  This didn't affect the results of the test suite
when extensions were allowed but it caused the test 'Inference rule
with explicit rule for prerequisite' to fail in POSIX mode.

2 files changed, 25 insertions, 24 deletions

diff --git a/miscutils/make.c b/miscutils/make.c
index 86d06e970..1414f869c 100644
--- a/miscutils/make.c
+++ b/miscutils/make.c
@@ -722,7 +722,7 @@ dyndep(struct name *np, struct rule *imprule)
                                         continue;
                                 if (!ip->n_tim.tv_sec)
                                         modtime(ip);
-                                if (chain ? ip->n_tim.tv_sec || (ip->n_flag & N_TARGET) :
+                                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) {
diff --git a/testsuite/make.tests b/testsuite/make.tests
index 7bb736ade..70c1231b9 100755
--- a/testsuite/make.tests
+++ b/testsuite/make.tests
@@ -59,6 +59,25 @@ x.p:
 '
 cd .. || exit 1; rm -rf make.tempdir 2>/dev/null
 
+# 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, though this test passed anyway.
+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
+
 # A macro created using ::= remembers it's of type immediate-expansion.
 # Immediate expansion also occurs when += is used to append to such a macro.
 testing "make appending to immediate-expansion macro" \
@@ -397,29 +416,11 @@ 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.
+# Austin Group defect report 875 (mentioned above) actually used
+# suffixes '.a .b .c'.  This doesn't matter in POSIX mode but it
+# caused a failure (now fixed) when chained inference rules were
+# allowed.  The '.a.c' and the built-in '.c.a' inference rules
+# resulted in a loop.
 mkdir make.tempdir && cd make.tempdir || exit 1
 touch test.a test.b
 testing "make proper handling of inference rules 2" \