From 6eeaf7485c656abb7f00635235c3a775c38010fa Mon Sep 17 00:00:00 2001
From: rofl0r <rofl0r@users.noreply.github.com>
Date: Wed, 27 Apr 2022 16:17:04 +0000
Subject: [PATCH] build: allow empty prefix

there was some concern that this will break windows' way of doing
file lookups relatively from the binary, rather than via hardcoded
locations, but so far each occurence adding e.g. "CA65_INC" to
the pathsearch is already shielded with an #ifndef _WIN32.

addressing #1726
---
 doc/Makefile     | 1 -
 libsrc/Makefile  | 1 -
 samples/Makefile | 1 -
 src/Makefile     | 3 +--
 4 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/doc/Makefile b/doc/Makefile
index bb8f551ad..bfdf0cce3 100644
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -46,7 +46,6 @@ clean:
 	$(RM) -r ../html ../info
 
 install:
-	$(if $(PREFIX),,$(error variable "PREFIX" must be set))
 ifeq ($(wildcard ../html),../html)
 	$(INSTALL) -d $(DESTDIR)$(htmldir)
 	$(INSTALL) -m0644 ../html/*.* $(DESTDIR)$(htmldir)
diff --git a/libsrc/Makefile b/libsrc/Makefile
index 177314bdf..2018de801 100644
--- a/libsrc/Makefile
+++ b/libsrc/Makefile
@@ -96,7 +96,6 @@ INSTALL = install
 
 define INSTALL_recipe
 
-$(if $(PREFIX),,$(error variable "PREFIX" must be set))
 $(INSTALL) -d $(DESTDIR)$(datadir)/$(dir)
 $(INSTALL) -m0644 ../$(dir)/*.* $(DESTDIR)$(datadir)/$(dir)
 
diff --git a/samples/Makefile b/samples/Makefile
index 9732cfac7..01ad6f983 100644
--- a/samples/Makefile
+++ b/samples/Makefile
@@ -525,7 +525,6 @@ INSTALL = install
 samplesdir = $(PREFIX)/share/cc65/samples
 
 install:
-	$(if $(PREFIX),,$(error variable "PREFIX" must be set))
 	$(INSTALL) -d $(DESTDIR)$(samplesdir)
 	$(INSTALL) -d $(DESTDIR)$(samplesdir)/geos
 	$(INSTALL) -d $(DESTDIR)$(samplesdir)/tutorial
diff --git a/src/Makefile b/src/Makefile
index 75b92394e..8356d0001 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -26,7 +26,7 @@ PROGS = ar65     \
 .SUFFIXES:
 
 bindir  := $(PREFIX)/bin
-datadir := $(if $(PREFIX),$(PREFIX)/share/cc65,$(abspath ..))
+datadir := $(PREFIX)/share/cc65
 
 CA65_INC = $(datadir)/asminc
 CC65_INC = $(datadir)/include
@@ -111,7 +111,6 @@ $(RM) /usr/local/bin/$(prog)
 endef # UNAVAIL_recipe
 
 install:
-	$(if $(PREFIX),,$(error variable "PREFIX" must be set))
 	$(INSTALL) -d $(DESTDIR)$(bindir)
 	$(INSTALL) ../bin/* $(DESTDIR)$(bindir)