Update Makefiles to make build more configurable - #22
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The top level Makefile did "export CFLAGS=-m64 -march=native -mtune=native
-Ofast -fopenmp -ansi -Wall -DBIT64 ... -I../include". A makefile
assignment beats the environment, so "CFLAGS=... make" was silently
ignored, and "make CFLAGS=..." replaced the whole line, taking -I../include
and the feature macros with it. There was no LDFLAGS at all, so linker
flags could not be passed either. Distributors have worked around this in a
variety of ways, most of them involving smuggling flags in through CC.
Move the settings into a new Makefile.inc, included by each Makefile, and
split the flags the build itself requires (CSDP_CPPFLAGS, CSDP_CFLAGS) from
the ones the user owns (CPPFLAGS, CFLAGS, LDFLAGS, LIBS). Neither can now
clobber the other. OpenMP gets its own OPENMP_CFLAGS/OPENMP_LIBS pair,
since it is spelled differently on macOS, and USEOPENMP/SETNUMTHREADS are
defined only when it is actually enabled -- they include <omp.h> and call
the OpenMP runtime.
Also:
- Drop -m64, -march=native, -mtune=native, -Ofast, -ansi and -static from
the defaults. -Ofast implies -ffast-math and on glibc links
crtfastmath.o, which sets FTZ/DAZ process-wide; that is a poor default
for a numerical solver. Pin -std=gnu99 in place of -ansi: the sources
use K&R function definitions, which C23 removed, so the standard has to
be pinned somewhere below C23. gnu99 is the lowest setting that still
makes an implicit function declaration an error, and GNU rather than
strict mode because the code calls POSIX interfaces that a strict mode
is not obliged to declare.
- Use $(MAKE) -C rather than "cd dir; make", so that the subdirectory
builds inherit the jobserver.
- Use $(AR) rather than a hardcoded ar, so that a cross build can pass
its own archiver, and add the "s" flag so the archive always carries an
index.
- Honor prefix, bindir and DESTDIR when installing, and use install(1)
rather than cp. Add TOOL_PREFIX for distributors who rename theta,
complement, graphtoprob and rand_graph to avoid clashes.
- Mark install as .PHONY, so that "make install" keeps working on case
insensitive filesystems, where the INSTALL file would otherwise satisfy
the target.
This requires GNU make, which upstream's Makefiles did not: the feature
probes need $(shell), and the conditionals need ifeq/ifneq. Every consumer
already uses it, and the FreeBSD port already sets USES=gmake.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Only the five programs were installed, and only to a hardcoded location: libsdp.a and the headers were left in the build tree, so a distribution could not ship anything that another package could link against. Install libsdp.a into $(libdir), the headers into $(includedir)/csdp, and a pkg-config file into $(pkgconfigdir). The headers keep including each other with quotes, so they work both in the build tree and after installation, where a quoted include resolves next to the including file. Consumers can therefore write either #include <csdp/declarations.h> #include "declarations.h" whichever suits them; csdp.pc puts both directories on the include path. Add the include guards that blockmat.h, index.h and parameters.h were missing, and extern "C" to all four, since they are public headers now. SHARED=yes additionally builds a shared library -- libsdp.so.0 on ELF systems, libsdp.0.dylib on macOS -- and the programs then link against it, since -lsdp prefers the shared library when both are present. The default is still a static build, so nothing changes for distributions that only want the programs. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
macOS names a shared library libsdp.<version>.dylib rather than libsdp.so.<version>, records an install name in the library itself instead of a soname, and builds it with -dynamiclib rather than -shared. Add that shape, selected by asking the compiler whether it defines __APPLE__ rather than by asking uname what we are running on, so that it is right when cross compiling as well as natively. Kept separate from the base shared library support, so that a distribution that only needs the ELF shape does not have to carry it. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Windows has no sonames and no symlinks, and names a shared library for its ABI version rather than its release version. The artifacts are a versioned DLL, which belongs next to the programs because that is where Windows looks for it, and an import library, which is what goes in $(libdir). Code there is always position independent, so -fPIC is not used. Which of the three shapes to build is decided by asking the compiler what it defines rather than by asking uname what we are running on, so this is correct when cross compiling with mingw as well as natively under MSYS2. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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We update the Makefiles to make things more configurable, which should be helpful for downstream package maintainers.
Here's a summary of the updates:
CFLAGSeither from the environment (which are currently ignored) or passed viamake CFLAGS=...(which currently overwrites flags we need like-I../include).BLAS_LIBS,OPENMP_CFLAGS, andOPENMP_LIBSfor configuring BLAS/LAPACK and OpenMP flags.BIT64,USESIGTERM, etc.) (this feature requires using GNU make)-ansito-std=gnu99so we can use Clang's OpenMP headers, which useinline.$(MAKE)instead ofmakefor the subdirectories.TOOL_PREFIXfor distros like Debian who rename the binaries, e.g.,theta->csdp-theta..PHONYtargets added, which fixes a problem on macOS wheremake installwouldn't run becauseINSTALLalready existed.The changes were tested on lots of different systems and compilers: https://github.com/d-torrance/Csdp/actions/runs/31973784789
🤖 AI Disclosure 🤖
Claude Code generated the first draft of the changes, but I made lots of tweaks.